you want the 5x62 model, from leviton, bryant, or hubbell. The model numbers are 5262 for 15 amp and 5362 for 20 amp (note, you can use 15 amp duplex receptacles on a 20 amp circuit, and 20 amp duplex receptacles are no more 'heavy duty' than 15 amp, the pin configuration is the only thing different) These are the federal spec 'industrial grade' type, the only thing better is hospital grade but for garage / shop use there is no additional benefit to make the extra cost worth it. Home stores are typically pretty expensive for these, I would try an electrical wholesaler.