This is an excellent condition 20 inch flattop Bushmaster upper with a Bushmaster flip-up front sight. It has approximately 300 rounds through it. It does have normal handling marks. Now the bad news. The front sight base has been shaved down and the flip-up is installed over it. This could be replaced by a new shaved gas block like the ones on the varminter rifles. This upper shoots great, it just has the shaved fsb. I'm asking $350 shipped for the complete upper with b/c/ch. I take PayPal at +3%. Let me know if you have any questions. Thanks.