Any idea what goes on here?

"a 100 rnd mag"It's a 100 rnd Drum mag , you need a winder to wind the spring inside the mag to load the .303 rnds , You don't want it? i'll take the part off your hands from you if you don't want to have it on your carrier , 100 rnd mags in Great shape go for over $700.00 USd's, I have 2, Cheers


BIG MIKE