I got a pair of cargo / mtb Pearl Izumi's and it had a sort of cycling short "insert" is the best way I can describe it. Mesh with padded chamois pad, and attached to the inside of the cargo's with two loops on each hip. I don't like the cargo's, so I just snipped the 2 loops, removed the mesh short "insert" and wear that under my regular shorts. It's very comfortable, with no undies and I think somewhat cooler on hot days than the regular spandex short.