Dimensions of the shackle in a
U-lock or padlock (see "Type").
In the first case, only two parameters are usually indicated — width and length (height), most often in that order, but sometimes vice versa. However, it is not difficult to determine where what size is — the length is longer, this is due to the purpose of the lock. It usually varies from 130 – 140 to 300 mm, width — from 80 to 115 – 120 mm. A larger shackle gives more options for attaching the bike (it will “get” further and be able to cover a larger object), however, the lock also turns out to be bulky and heavy. Shackle thickness for U-locks is listed separately (see below).
But in padlocks, all three sizes are usually called, including the thickness. Here, the width and length most often differ slightly, by a couple of millimetres, although there are exceptions, with an elongated bow. Anyway, this parameter is not as important for such locks as for U-locks: firstly, hinged models are miniature by definition, and secondly, the difference in size is not particularly critical for their main purpose (shackles 20x20 and 30x30 mm are the same effectively fasten the ends of the "average" cable or chain).
