usps

Anyone ever hear the US Postal Service? Theres a large facility close to me and I've scanned 406 to 408 and the Federal band on SDS200 and I think I've only ever heard some kind of truck yard freq? I think it's DMR, but I've never found anything else.

Does anyone know the frequency or frequencies for the Postal Police in the Bay Area and where they are located? I am very interested in them. I think they are just in San Francisco and Oakland but if anyone has more information about their radio frequencies/type or locations please let me know.