Square drive size
The size of the "seat" for which the socket heads included in the package are designed (see below), in other words, the size of the square hole on the back of the head used for installation on a ratchet, wrench or other similar tool. Accordingly, the tool for working with heads supplied in the kit has the same dimensions of the landing square; and in the absence of such tools in the kit, data on the size of the heads will be useful for its selection.
There is a generally accepted standard for these sizes, providing for the designation in fractions of an inch — from 1/4 "to 1". Thanks to this, heads and tools from different sets can be quite compatible — just matching in size is enough. Most often in modern hand sets there are options in 1/4 "and 1/2", a little less often — 3/4" and 3/8". Some sets include several variants of the landing square at once.
Socket heads sizes (E-profile)
Working size range of E-profile sockets (see above) supplied with the kit. This parameter allows you to evaluate how the heads fit the dimensions of the fasteners with which they are planned to be used.
Adapter
An adapter for docking seemingly incompatible elements from a set. For example, socket heads with an unsuitable landing square on a ratchet, screwdriver handle or in a drill driver.
The adapter provides full-fledged work with all the required list of tools from the set.
Hex wrenches size
Working size range of hex wrench sizes (see above) supplied with the kit. This parameter allows you to evaluate how the keys fit the dimensions of the fasteners with which they are planned to be used.
Also in kit
Additional items included with the toolbox but not listed above. Here are some of those items:
— Adapter. Adapter from one type of mount to another. Quite often, adapters are designed to fit magnetic bits (see above) with a hex shank into a tool that uses a landing square, but there may be other options — for example, adapters between different sizes of the mentioned squares (see above).
— Holder for bits. A specific type of adapter designed to mount bits with a conventional hex shank in screwdrivers where a shank with a notch for a retainer is required. In extreme cases, they can also be used as improvised screwdrivers. Several holders can be supplied, in such cases they usually differ in length.
— Level. A tool for assessing the position of a particular surface. The simplest levels are for testing whether a surface is horizontal or not; however, tool kits usually include more advanced fixtures that allow you to also control verticality, and in some cases also check compliance with a 45 ° tilt and even measure a specific angle of deviation from the horizontal / vertical.
— Depth limiters. They are used together with drills (see above). They allow you to set the maximum drilling depth — the tool simply will not go further; this is useful in cases where you need to make holes of a given depth.
— Telescopic magnetic probe. A device in the form of an extendable rod (like an antenna or a pointer) with a strong permanent magnet at...the end. Facilitates the collection of small metal parts — for example, crumbled bolts or bits — including and in hard-to-reach places (like the space under the cabinet or a narrow gap between the boards).
— Lamp. Classic flashlight for lighting in dark places.
— Tester. He's an indicator. A specialized screwdriver for searching for a phase in electrical networks during electrical work. The indicator rod is almost completely covered with insulation, and a light bulb is located in the transparent handle. Such a device can also be used as a classic screwdriver, but it is not designed for applying great efforts — the main purpose is to search for the phase.
— Fastening devices — for example, screws with dowels. In normal cases, it is more convenient to buy fasteners separately, for specific needs; however, there are situations when the "emergency stock" provided in the kit is very handy.
This list is not exhaustive — manufacturers may provide other equipment, sometimes very specific.
Weight
The total weight of the tool kit. Indicated with a case, stand or other storage/transportation device (see Tool Storage). First of all, you should pay attention to this parameter if you plan to often carry the kit over long distances — the lighter the weight, the easier it will be to do. At the same time, extensive sets inevitably turn out to be weighty.