Good quality, british manufactured mortice bathroom sashlock.
This bathroom lock is 72mm centres and is typically used in conjunction with lever on rose applications, mainly in architectural environments and/or where the advice of Document M, BS8300 and the DDA have to be met.
The dimension in the options relates to the case depth (A).
The rebate kit is in the related products (below) and is for a 1/2" rebate.