Today I stumbled across a 12 ga. Remington Model 11 mfg'd in 1920. It has a 20 inch barrel, and has serial # 217,XXX. It's in nice shape. I learned that magazine extensions for 870s fit if you add a 1/8 in. spacer. I tried the Scattergun Tech +2 extension from my 870 and it does fit. I'm very happy. I paid $249 plus tax. I might have overpaid a bit, but I wanted it. Anyone have one?