The General No. 142 6-inch dial caliper does direct reading of .01″ (outer scale) and 1/64″ (inner scale) on its dial (plus mm readings on the bar scale, but — without getting into that whole metric thing — I don’t find this “feature” very convenient). It can do inside, outside, depth, and step measurements. Its fiberglass-reinforced plastic body makes it a good choice for damp/wet environments. You can pick one up for around $24.