United Kingdom

Thunderbolt v4 port laptops

 prices on 427 models  
Thunderbolt v4
clear
Show
Laptop Lenovo ThinkPad X1 Carbon Gen 11
  • display 14 ", 1920x1200 (16:10) / 2880x1800 (16:10)
  • CPU Intel, Core i5 / Core i7
  • GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs
  • RAM 16 / 32 GB
  • storage 256 - 1024 GB
  • weight 1.12 kg
  • Intel Iris Graphics
Lenovo ThinkPad X1 Carbon Gen 11
display 14 ", 1920x1200 (16:10) / 2880x1800 (16:10), CPU Intel, Core i5 / Core i7, GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs, RAM 16 / 32 GB, storage 256 - 1024 GB, weight 1.12 kg, Intel Iris Graphics
21HM004QUK
Core i51335U16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £999.00 .. £2,027.00 
21HM0064PB
Core i51335U16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe512 GB £1,823.19
21HM004FMH
Core i71355U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,483.54
21HM003UUK
Core i71355U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,615.99 .. £3,132.00 
21HM0077UK
Core i71355U32 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,800.00 .. £1,831.00 
21HM0072UK
Core i71355U32 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe1024 GB £1,879.99 .. £2,644.00 
21HMCTO1WW
Core i71365U32 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe256 GB £1,850.99 .. £2,437.00 
Laptop Asus ExpertBook B9 B9400CEA
  • display 14 ", 1920x1080 (16:9)
  • CPU Intel, Core i7
  • GPU Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 256 GB
  • weight 0.88 kg
  • Intel Iris Graphics
Asus ExpertBook B9 B9400CEA
from £670.94
display 14 ", 1920x1080 (16:9), CPU Intel, Core i7, GPU Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 256 GB, weight 0.88 kg, Intel Iris Graphics
400CEA-KC0182X
Core i71165G716 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe256 GB £670.94
Laptop Lenovo ThinkPad T14s Gen 4 Intel
  • display 14 ", 1920x1200 (16:10)
  • CPU Intel, Core i5 / Core i7
  • GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 256 / 512 GB
  • weight 1.25 kg
  • Intel Iris Graphics
Lenovo ThinkPad T14s Gen 4 Intel
display 14 ", 1920x1200 (16:10), CPU Intel, Core i5 / Core i7, GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 256 / 512 GB, weight 1.25 kg, Intel Iris Graphics
21F60037UK
Core i51335U16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £849.98 .. £2,001.00 
21F6003WUK
Core i71355U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,259.99 .. £2,301.00 
Laptop Razer Book 13 2020
  • display 13.4 ", 1920x1200 (16:10)
  • CPU Intel, Core i7
  • GPU Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 512 GB
  • weight 1.4 kg
  • Intel Iris Graphics
Razer Book 13 2020
display 13.4 ", 1920x1200 (16:10), CPU Intel, Core i7, GPU Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 512 GB, weight 1.4 kg, Intel Iris Graphics
‎R..57MWM2-R3W1
Core i71165G716 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,483.18
Laptop Lenovo ThinkBook 13x G2 IAP
  • display 13.3 ", 2560x1600 (16:10)
  • CPU Intel, Core i5 / Core i7
  • GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs
  • RAM 8 / 16 GB
  • storage 256 / 512 GB
  • weight 1.2 kg
  • Intel Iris Graphics
Lenovo ThinkBook 13x G2 IAP
display 13.3 ", 2560x1600 (16:10), CPU Intel, Core i5 / Core i7, GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs, RAM 8 / 16 GB, storage 256 / 512 GB, weight 1.2 kg, Intel Iris Graphics
21AT000JUK
Core i51235U8 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £499.97 .. £1,099.00 
21AT000EUK
Core i71255U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £949.99 .. £1,300.00 
Laptop Lenovo ThinkPad X1 Nano Gen 2
  • display 13 ", 2160x1350 (16:10)
  • CPU Intel, Core i5 / Core i7
  • GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 256 / 512 GB
  • weight 0.97 kg
  • Intel Iris Graphics
Lenovo ThinkPad X1 Nano Gen 2
display 13 ", 2160x1350 (16:10), CPU Intel, Core i5 / Core i7, GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 256 / 512 GB, weight 0.97 kg, Intel Iris Graphics
21E80026UK
Core i51240P16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £1,930.00
21E80022UK
Core i71260P16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £2,180.94 .. £2,200.00 
Laptop Huawei MateBook 16s 2023
  • display 16 ", 2520x1680 (3:2)
  • CPU Intel, Core i9
  • GPU Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 1024 GB
  • weight 2 kg
  • Intel Iris Graphics
Huawei MateBook 16s 2023
display 16 ", 2520x1680 (3:2), CPU Intel, Core i9, GPU Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 1024 GB, weight 2 kg, Intel Iris Graphics
53013SCQ
Core i913900H16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe1024 GB £1,093.00 .. £1,475.00 
Laptop Lenovo ThinkPad T14 Gen 4 Intel
  • display 14 ", 1920x1200 (16:10)
  • CPU Intel, Core i5 / Core i7
  • GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs
  • RAM 16 / 32 GB
  • storage 256 - 1024 GB
  • weight 1.4 kg
  • Intel Iris Graphics
Lenovo ThinkPad T14 Gen 4 Intel
display 14 ", 1920x1200 (16:10), CPU Intel, Core i5 / Core i7, GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs, RAM 16 / 32 GB, storage 256 - 1024 GB, weight 1.4 kg, Intel Iris Graphics
21HD003FUK
Core i51335U16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £945.99 .. £1,901.00 
21HD0043GE
Core i51335U16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe512 GB £982.15
21HD007HSP
Core i51335U16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe512 GB £1,049.37 .. £1,359.00 
21HD004MUK
Core i71355U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,099.99 .. £2,200.00 
21HD007LSP
Core i71355U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,200.23 .. £1,294.00 
21HD005XGE
Core i71355U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £2,414.16
21HD0051SP
Core i71355U32 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe1024 GB £1,254.79 .. £1,308.00 
21HD00A7SP
Core i71355U32 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe1024 GB £1,701.99
Laptop HP EliteBook 650 G9
  • display 15.6 ", 1920x1080 (16:9)
  • CPU Intel, Core i7
  • GPU Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 512 GB
  • weight 1.74 kg
  • Intel Iris Graphics
HP EliteBook 650 G9
display 15.6 ", 1920x1080 (16:9), CPU Intel, Core i7, GPU Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 512 GB, weight 1.74 kg, Intel Iris Graphics
6A1N4EA
Core i71255U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,103.50 .. £1,149.00 
Laptop Lenovo ThinkPad X13 Yoga Gen 4
  • display 13.3 ", 1920x1200 (16:10)
  • CPU Intel, Core i5 / Core i7
  • GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 256 / 512 GB
  • weight 1.21 kg
  • Intel Iris Graphics
Lenovo ThinkPad X13 Yoga Gen 4
display 13.3 ", 1920x1200 (16:10), CPU Intel, Core i5 / Core i7, GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 256 / 512 GB, weight 1.21 kg, Intel Iris Graphics
21F20011UK
Core i51335U16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £1,180.00 .. £2,420.00 
21F2001EUK
Core i71355U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,621.55 .. £2,644.00 
Laptop Lenovo ThinkPad T15 Gen 2 Intel
  • display 15.6 ", 1920x1080 (16:9)
  • CPU Intel, Core i5
  • GPU Iris Xe Graphics G7 80EUs
  • RAM 8 GB
  • storage 256 GB
  • weight 1.81 kg
  • Intel Iris Graphics
Lenovo ThinkPad T15 Gen 2 Intel
display 15.6 ", 1920x1080 (16:9), CPU Intel, Core i5, GPU Iris Xe Graphics G7 80EUs, RAM 8 GB, storage 256 GB, weight 1.81 kg, Intel Iris Graphics
20W400MVUK
Core i51135G78 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £1,143.99 .. £1,229.00 
20W4008YUK
Core i51135G78 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £1,255.52 .. £1,282.00 
Laptop HP EliteBook 1040 G9
  • display 14 ", 1920x1200 (16:10)
  • CPU Intel, Core i7
  • GPU Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 512 GB
  • weight 1.16 kg
  • Intel Iris Graphics
HP EliteBook 1040 G9
display 14 ", 1920x1200 (16:10), CPU Intel, Core i7, GPU Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 512 GB, weight 1.16 kg, Intel Iris Graphics
5P6Q0EA
Core i71255U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £899.90 .. £990.00 
6F690EA
Core i71255U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,023.59
Laptop Asus ExpertBook B5 B5302CEA
  • display 13.3 ", 1920x1080 (16:9)
  • CPU Intel, Core i5
  • GPU Iris Xe Graphics G7 80EUs
  • RAM 8 GB
  • storage 256 GB
  • weight 1.1 kg
  • Intel Iris Graphics
Asus ExpertBook B5 B5302CEA
display 13.3 ", 1920x1080 (16:9), CPU Intel, Core i5, GPU Iris Xe Graphics G7 80EUs, RAM 8 GB, storage 256 GB, weight 1.1 kg, Intel Iris Graphics
302CEA-EG0391R
Core i51135G78 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £473.90 .. £922.00 
Laptop Lenovo ThinkPad X1 Nano Gen 1
  • display 13 ", 2160x1350 (16:10)
  • CPU Intel, Core i5
  • GPU Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 256 GB
  • weight 0.91 kg
  • Intel Iris Graphics
Lenovo ThinkPad X1 Nano Gen 1
display 13 ", 2160x1350 (16:10), CPU Intel, Core i5, GPU Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 256 GB, weight 0.91 kg, Intel Iris Graphics
20UN00DYUK
Core i51130G716 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe256 GB £611.46 .. £638.00 
Laptop HP EliteBook 840 G9
  • display 14 ", 1920x1200 (16:10)
  • CPU Intel, Core i5 / Core i7
  • GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs
  • RAM 8 / 16 GB
  • storage 256 / 512 GB
  • weight 1.36 kg
  • Intel Iris Graphics
HP EliteBook 840 G9
display 14 ", 1920x1200 (16:10), CPU Intel, Core i5 / Core i7, GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs, RAM 8 / 16 GB, storage 256 / 512 GB, weight 1.36 kg, Intel Iris Graphics
6T132EA
Core i51235U8 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £829.99 .. £899.00 
6T1A4EA
Core i51235U8 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £941.79 .. £972.00 
7X9C7AA
Core i51235U16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe512 GB £846.00
6T1A1EA
Core i51235U16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £941.79 .. £1,619.00 
6T198EA
Core i51245U16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £649.00 .. £1,055.00 
6T1H6EA
Core i71255U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £789.90 .. £1,158.00 
Laptop Lenovo ThinkPad X13 Yoga Gen 3
  • display 13.3 ", 1920x1200 (16:10)
  • CPU Intel, Core i5 / Core i7
  • GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 256 / 512 GB
  • weight 1.2 kg
  • Intel Iris Graphics
Lenovo ThinkPad X13 Yoga Gen 3
display 13.3 ", 1920x1200 (16:10), CPU Intel, Core i5 / Core i7, GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 256 / 512 GB, weight 1.2 kg, Intel Iris Graphics
21AW0032UK
Core i51235U16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £899.97 .. £1,824.00 
21AW003BUK
Core i71255U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,818.18
Laptop Lenovo ThinkBook 14 G2 ITL
  • display 14 ", 1920x1080 (16:9)
  • CPU Intel, Core i5 / Core i7
  • GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs
  • RAM 8 / 16 GB
  • storage 256 / 512 GB
  • weight 1.4 kg
  • Intel Iris Graphics
Lenovo ThinkBook 14 G2 ITL
display 14 ", 1920x1080 (16:9), CPU Intel, Core i5 / Core i7, GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs, RAM 8 / 16 GB, storage 256 / 512 GB, weight 1.4 kg, Intel Iris Graphics
20VD00UNUK
Core i51135G78 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £739.01
20VD00USUK
Core i71165G716 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £889.01
Laptop Lenovo ThinkPad L14 Gen 2 Intel
  • display 14 ", 1920x1080 (16:9)
  • CPU Intel, Core i5 / Core i7
  • GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs
  • RAM 8 / 16 GB
  • storage 256 / 512 GB
  • weight 1.59 kg
  • Intel Iris Graphics
Lenovo ThinkPad L14 Gen 2 Intel
display 14 ", 1920x1080 (16:9), CPU Intel, Core i5 / Core i7, GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs, RAM 8 / 16 GB, storage 256 / 512 GB, weight 1.59 kg, Intel Iris Graphics
20X100LWUK
Core i51135G78 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £602.49 .. £640.00 
20X100L0UK
Core i71165G716 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £917.99 .. £1,173.00 
20X1003VUK
Core i71165G716 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,149.00 .. £1,201.00 
Laptop Asus ExpertBook B5 Flip OLED B5302FEA
  • display 13.3 ", 1920x1080 (16:9)
  • CPU Intel, Core i7
  • GPU Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 512 GB
  • weight 1.3 kg
  • Intel Iris Graphics
Asus ExpertBook B5 Flip OLED B5302FEA
from £805.64
display 13.3 ", 1920x1080 (16:9), CPU Intel, Core i7, GPU Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 512 GB, weight 1.3 kg, Intel Iris Graphics
302FEA-LF1020X
Core i71165G716 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £805.64
Laptop HP Elite Dragonfly G3
  • display 13.5 ", 1920x1280 (3:2)
  • CPU Intel, Core i7
  • GPU Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 512 GB
  • weight 0.99 kg
  • Intel Iris Graphics
HP Elite Dragonfly G3
display 13.5 ", 1920x1280 (3:2), CPU Intel, Core i7, GPU Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 512 GB, weight 0.99 kg, Intel Iris Graphics
5P6P6EA
Core i71255U16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,506.99 .. £1,788.00 
Laptop Lenovo ThinkPad X13 Yoga Gen 2
  • display 13.3 ", 2560x1600 (16:10)
  • CPU Intel, Core i5
  • GPU Iris Xe Graphics G7 80EUs
  • RAM 8 GB
  • storage 256 GB
  • weight 1.2 kg
  • Intel Iris Graphics
Lenovo ThinkPad X13 Yoga Gen 2
display 13.3 ", 2560x1600 (16:10), CPU Intel, Core i5, GPU Iris Xe Graphics G7 80EUs, RAM 8 GB, storage 256 GB, weight 1.2 kg, Intel Iris Graphics
20W8002KUK
Core i51135G78 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £1,329.00
Laptop Asus ExpertBook B5 B5402CVA
  • display 14 ", 1920x1080 (16:9)
  • CPU Intel, Core i7
  • GPU Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 512 GB
  • weight 1.29 kg
  • Intel Iris Graphics
Asus ExpertBook B5 B5402CVA
display 14 ", 1920x1080 (16:9), CPU Intel, Core i7, GPU Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 512 GB, weight 1.29 kg, Intel Iris Graphics
402CVA-KII715X
Core i71360P16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £863.97 .. £1,377.00 
Laptop Acer Chromebook Spin 713 CP713-3W
  • display 13.5 ", 2256x1504 (3:2)
  • CPU Intel, Core i3 / Core i5
  • GPU Iris Xe Graphics G7 80EUs / UHD Graphics Xe G4 48EUs
  • RAM 8 GB
  • storage 256 GB
  • weight 1.45 kg
  • Intel HD Graphics / Intel Iris Graphics
Acer Chromebook Spin 713 CP713-3W
display 13.5 ", 2256x1504 (3:2), CPU Intel, Core i3 / Core i5, GPU Iris Xe Graphics G7 80EUs / UHD Graphics Xe G4 48EUs, RAM 8 GB, storage 256 GB, weight 1.45 kg, Intel HD Graphics / Intel Iris Graphics
CP-3W-326R
Core i31115G48 GBUHD Graphics Xe G4 48EUsSSD M.2 NVMe256 GB £567.84 .. £699.00 
CP-3W-52AL
Core i51135G78 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £588.97 .. £718.00 
Laptop Lenovo ThinkPad T14s Gen 3 Intel
  • display 14 ", 1920x1200 (16:10)
  • CPU Intel, Core i5 / Core i7
  • GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs
  • RAM 16 GB
  • storage 256 / 512 GB
  • weight 1.21 kg
  • Intel Iris Graphics
Lenovo ThinkPad T14s Gen 3 Intel
display 14 ", 1920x1200 (16:10), CPU Intel, Core i5 / Core i7, GPU Iris Xe Graphics G7 80EUs / Iris Xe Graphics G7 96EUs, RAM 16 GB, storage 256 / 512 GB, weight 1.21 kg, Intel Iris Graphics
21BR0010UK
Core i51240P16 GBIris Xe Graphics G7 80EUsSSD M.2 NVMe256 GB £874.99 .. £1,534.00 
21BR00F0PB
Core i71260P16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,226.42
21BR001CUK
Core i71260P16 GBIris Xe Graphics G7 96EUsSSD M.2 NVMe512 GB £1,446.08 .. £1,831.00 
24 more item(s)
Filters
Price
from£ up to£ 
Brands
Device type
Features
Screen size
Screen resolution
Screen type
Screen surface
Refresh rate
Display features
CPU
CPU code name
CPU series
Processor cores
CPU frequency
RAM
Max. RAM
RAM type
RAM frequency
RAM slots
GPU
Dedicated GPU
Max. connected monitors
Drive
Drive size
Weight
Inputs & Outputs
USB A
USB type C
Network connection
Multimedia
Release year
more
Extra features & security
Aspect ratio
Brightness
Colour gamut
Keyboard backlight colour
Operating system
Material
Colour
Clear parameters