They go on the extractor to increase the tension to assist in extraction on your .223/5.56 rifle.
Place them over the extractor spring without removing it.
They also fit 1911 grip screws to prevent the common problem of them becoming loose.
This auction is for 12 O-Rings and free shipping!
These usually cost $3++ EACH at your local gun store!
They work like the D-Fender D-Ring that can cost over $10 for one O Ring!
Make sure this part will fit your rifle before purchasing.
Commonly Referred to as size #60
Part #: AS568A Dash Number 006
Size: 1/4 in OD x 1/8 in ID x 1/16 in