Looks like a device with two drums each capable of no more than 10 rounds to me...
No different than a coupler.
save your $$$ .. find some 1/4 " plastic and cut to fit in the recess of the mag bottom and epoxy it in and pop another mag on the other side ..
piece of cake .. .. not hard to double stack 10/22 rotor mags ...
pew pew pew .. eject ... flip .. pew pew pew ..
i did the same with all my Mini14 10 rnd mags .. little thinking and some epoxy .. there back to back .. shoot , flip , shoot ..
View attachment 37587 Got mine today.
Probably by the 26thRange report
Range report
Yeah I'm interested to know how they work as well.Probably by the 26th