Filter viewing area (WxH)
The size of the transparent part of the light filter — the "working window", the area through which the welder sees the place of work. A larger working window provides ease of use and a wide field of view, but it significantly affects the cost of the mask and somewhat reduces the strength of the light filter.
Filter cartridge dimensions (WxH)
The overall dimensions of the light filter for which the mask is designed, taking into account the working window, protrusions for mounting, batteries, sensors and other structural elements. This indicator is especially important for models that are not equipped with light filters: without knowing the size, it is very difficult to choose the right cartridge. In other cases, data on the size of the cartridge is needed mainly when looking for a replacement for a failed colour filter.
Design features
— Backlight. Illumination system built right into the mask. This feature is very convenient when working in low light conditions: the backlight does not take up the hands (unlike hand-held flashlights) and does not create problems with wearing a mask (unlike headlamps), while the beam of light is always directed to where the welder's head is turned. On the other hand, such a system requires its own power supply. Therefore, it is used only in "chameleons", while the operation of the backlight additionally consumes battery power.
