The standard length of the Jackloc cable is 200mm. The opening gap is determined by the relative fixing of the two blocks, one at either end of the cable. Health and Safety recommend a maximum opening of 100mm.
This Jackloc Can be fitted either vertically or horizontally. The lock is supplied with size 8 hardened steel security clutch screws. Once fitted they cannot be unscrewed. If you prefer to use different screws, please refer to your window manufacturer. It is usually advisable to drill pilot holes with a 2.5mm drill bit.
The key must be used to unlock and re-lock the restrictor. Never leave the key in the lock.