enblethen wrote:
Gdetrailer:
The OP says he bought a single pole breaker not a two pole tandem.
No where did I mention or post "two pole tandem" which would have both breaker handles tied together and would be for 240V usage like this pix..

and in reality a double pole breaker is not referred to a "tandem" because the handles are tied together and the breaker is twice the size of a standard 1" breaker to catch both L1 and L2
OP posted this pix..
DarkSkySeeker wrote:
All of the breakers are the same manufacturer, they just have different limits.

All of the breakers in that pix are single pole
tandem and I suspect the OP had to buy a single pole
tandem in order to replace the old breaker.
Most breaker panels in RVs will be full and to maximize the amount of circuits they will use single pole tandems in the pix the OP provided and the examples I have shown other than the double pole 240V breaker in this post..