The Excel Hardware 63mm (2.5") Stainless Steel Bolt Through Tubular Mortice Latch SSS is for use with internal door handles on backplate & door handles on rose. It has a standard case size of 63mm with a 44mm backset. It can be used on new doors & as replacements for old, worn latches. It will accept a standard 8mm square spindle. This latch is made from zinc alloy & has a satin stainless steel finish. Other Variations The latch is also available with a 76mm case & this can be found in the related products.