Frame-and-panel router bits sets are thickness specific, so the bits you use for a cabinet door may not be the same set you need for a delicate jewelry box made from thinner material. Scaled-down frame-and-panel sets, like this new one from Freud, solve the problem. Various companies make these miniature versions. In function, they're identical to their larger kin, and setup is the same. The difference is simply in the profile. It's made smaller so it will fit into thinner stock, typically material from 3/8 in. to 11/16 in. thick. Just as larger profiles won't work in thin material, though, these smaller bits won't work in thick material. But sometimes, a little bit'll do ya.
Freud, (800) 472 7307, www.freudtools.com, 2+2 Mini Raised-Panel Set, #97-904, $205.