Sorry about the typo. I meant to say the current production 16 ga. 870 uses the 12 ga. stock NOT the 20ga. The current production 20 ga. is a smaller stock and receiver which was once known at the light weight or LWT. I have 12, 16 and 20 870's and it is clear to see the 12 & 16 are same size and the 20ga. is smaller.