With 8mm spindle. The 7300 Mechanical Digital Lock from Lockey is a medium duty reversible lock with an easy code change function. This model is supplied with an 8mm square spindle. It has over 7,000 potential combinations of 3 to 7 digits and it is suitable for doors that are 35mm to 55mm in thickness. The 7300 features passage function as well as being supplied with the required fixings.. For use with various din locks/lock cases (supplied separately). Passage function. Supplied with 8mm square bar spindle. Easy code change