With a shallow depth of cut of just 12.7mm, and diameter of 31.7mm, the CMT mortising/straight router bit is the ideal bit for cleaning out mortices. The shallow depth means it cat cut shallow to deep mortices easily without the need to have a particularly thick template, and the extra wide diameter means a cleaner cut with the router never being overworked.
They also make an easy job of piece work in both natural wood and wood composites.