Cigg lighters in modern cars use 30 Amps, although 10/15 should be enough for most things if you won't use a lighter.
All devices working with a cigaret lighter socket have a
small tube fuse directly connected to the spring loaded pin that makes contact with the positive side of the cigarette lighter.
Might be good to know in case one of your devices stop working but the fuse in your truck/car is intact!