Purchased this product and it arrived in a timely manner. I attempted to install the charging handle several times but it would not engage. I inspected it and found that the roll pin holding the extended lever was protruding way past the flush point and had to do some serious filing to get it to work. I believe that this is something that should have been noticed during the final product inspection and that there should have been no need for any alteration of the product. After "fixing" the problem the item worked as advertised.