Rifflers are double ended rasps. Auriou offer 4 lengths with 6 shape combinations. Each length is a particular grain. Auriou rifflers are very popular with anyone who needs to add or refine detail on their work including sculptors, woodturners, gunstock makers, decoy duck makers, wildfowl carvers etc.

Top tip - the 7" & 8" are the most poplular.
Go for the longer one (10") only if you are doing large scale work and for the smallest size only if you are doing very fine detail work.