I have for sale 6 of the original Master Mold Thermold magazines 5.56/.223 for AR-15's or M16's. These are the ribbed side style and they are used but work excellently. I just can't use them in my custom fancy AR-15 lower but they work on all standard milspec AR lowers. I've had them for years and they worked on everything i used them in including a robinson xcr, sig 556, various AR-15's and even on a Daewoo K1. take all 6 for $100. OBO. looks like this pic. This is not the actual mags but looks the same.