Total number of items
The total number of core items included in the set.
In this case, the main items are all devices that are directly used during work: non-separable tools (traditional wrenches, hammers, pliers ...), elements of collapsible tools (for example, a ratchet for removable heads and 5 such heads will be considered 6 units) , as well as accessories (such as extensions or universal joints). Additional accessories — such as lights — may or may not be included in this count, depending on the manufacturer; however, there are usually few such accessories, and they do not fundamentally affect the total number of items.
The most modest modern tool kits include
up to 25 units. However, such kits are very popular — they are inexpensive and at the same time can be very versatile.
25 – 50 items is still quite a small number,
50 – 75 pcs can be called an average,
76 – 100 items are more than average, and the most extensive modern sets can include
100 – 150 items or even
more.
The general rules for choosing this parameter are obvious: a more extensive set, usually, is more multifunctional, but more expensive, weighs more and takes up more space. It is also worth bearing in mind that with a similar number of items, the specific assortment of these items in differ
...ent sets may be different; so when choosing, it is worth specifying not only the number of tools, but also their specific composition.Open end wrenches
The number of open-
end wrenches supplied in the kit. Note that some modern kits
only include open-end wrenches, without any other fixtures or accessories.
Open-end wrenches are called classic wrenches with a U-shaped working profile. When working, they cover the part from three sides (on two — if the key clings to the very tips of the "horns"). Because of this, such wrenches lose to ring wrenches in terms of uniformity of impact and are less suitable for work in which significant efforts are required (horn tools are more likely to break off the part). However, in most cases this shortcoming is not critical. In addition, the U-shape of the profile allows you to work with pipelines, hoses, etc., on which it is impossible to put a spanner wrench, and also makes it possible to hold an open-end tool during operation similar to a screwdriver — not perpendicular to the axis of rotation of the fastener, but parallel. Due to this, in some cases, this type of key may well replace the end keys (see below).
Note that most often modern open-end wrenches are made double-sided, with working profiles of different sizes at different ends. As for the quantity, it is worth considering here: sets with the same number of keys of the same type may differ in the specific sizes of these tools. Such nuances should be clarified before buying separately.
Wrench sizes
Dimensions of the wrenches supplied in the set. Specified as a range — from the minimum to the maximum size. In this case, the specific distribution of different types of keys over the range may be different. An example is the following set: 17 open-end wrenches, 5 box wrenches, size range 6 – 24 mm. In such a set, box wrenches are almost guaranteed not to cover the entire range of sizes, but for open-end wrenches, this is quite likely. Such details can be specified separately.
Also note that a wrench size of
24mm or more is considered quite large for today's general purpose tools. However, on the market you can find sets that include wrenches for
27 mm,
30 mm and even
32 mm.
