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 (6 points)
Working size range of hex 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.
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.
Bit sizes
Varieties of bits (see above) included in the set.
Note that this paragraph specifies not just the size, but also the type of slot for which this or that bit is designed. This type is indicated by a letter index followed by a number describing the size — for example, SL5. Here are the most popular designations found in modern bits:
— SL. Flat bits for straight slot. The size is indicated in millimetres.
— Ph. Classic cross bits. The size is indicated by a conditional number.
— P.Z. Bits for a modified cross slot with improved engagement, have additional edges. The size is indicated by a conditional number.
— TX, T. Torx bits, with six-pointed sprocket tips. The size is indicated by a conditional number.
— H. Hex bits, with hex tips. The size is indicated in millimetres.
If there is more than one bit of a certain type in the set, the number is specified after the designation, for example, PH2x2.
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.
Ratchet wrench
The number
of ratchet wrenches in the toolbox. The name of such tools comes from the ratchet mechanism installed in them, which emits a characteristic crack during operation.
First of all, we emphasize that the term "ratchet wrench" in this case means a composite tool — in the form of a handle with a seat for interchangeable nozzles (for example, socket heads of one type or another — see above). Do not confuse such a tool with more traditional wrenches that have similar equipment (for more on such wrenches, see "Ratchet (ratchet)"). Nevertheless, the meaning of the ratchet mechanism in this case is absolutely the same: thanks to it, the ratchet rotates the fastener only when turned in one direction, while the captured part remains motionless during the reverse movement. Thus, for constant rotation of the fastener in one direction, it is enough to swing the tool back and forth — this is much more convenient than periodically rearranging it or turning it full 360 °. The change of direction is usually carried out by a switch built into the ratchet.
Several ratchet wrenches included in one set, usually, differ in the size of the landing square (see above) and the length of the handle itself.
Screwdriver handle
Number of
screwdriver handles supplied with the tool kit.
Such handles, in fact, are screwdrivers without a tip — in its place there is a seat for a bit. It can be either a square (see above) or a hexagon socket, often magnetic; in fact, the presence of more than one handle in the kit is typical mainly for cases where different types of fasteners are used. Also note that, in addition to fixed mounts, in which the bit is fixed rigidly, there are also reversible devices — with a ratchet mechanism, similar in operation to ratchets (see above).
Theoretically, bits can be used with other types of tools — for example, the ratchets described above — and in many sets this possibility is directly provided. At the same time, it is work in the format of a screwdriver that is considered the classic option, and often it is he who is optimal.
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.
Dimensions
The dimensions of the entire set, namely the case, lodgment, cassette, etc. storage accessory (see paragraph above) with tools installed inside. Allows you to understand how much space the model will occupy and whether it can be placed in a complete set in one place or another.