Are you saying the power INLET has the same kind of "pins" (Blades, contacts whatever you want to call them) as teh cord on your TV, Computer or Microwave?
If so that is a 15 amp plug/inlet
Use a 12 GA extension cord (Lowes, Home Depot) and the 20 amp outlet on the pedestal. In the off case you have a site with no 20 amp outlet (Been there) carry a 15 to 30 PUCK or Dogbone style, this is the only case were I like PUCK type adapters
Dogbones are a plug and a socket with cord between
Puck are plug and socket in one.
In the basement of my motorhome.. Is a 30 amp cord, tt-30 plug with a distriution box on the other end.... My past trailers one had a common 15 amp inlet and the other a 20 amp twist lock.. Guess what I used.