spacers or carriers...?

[crazyjoe12]

so im trying to get my retro valve and lvl 10 tuned right. are spacers for lvl 7 bolt and carriers for the lvl 10? or are spacers for classic valves and carriers are for x and rt? is there a difference or can i use either?

[Watcher]

Spacers are for level 7, any automag classic to modern.

Only the level 10 uses the carriers.