TOPS nylon sheaths fails to match up to the quality of the knives, in my opinion. I´ve got a TOPS US combat knife which I absolutely love, but I need to make a proper leather sheath for it eventually. While not exactly flimsy, the nylon sheath insert is poorly made. Instead of a flat "tube" like in the sheath that came with my BK17 it has a molded plastic insert that can´t easily be tightened for better retention and makes it impossible to flip the knife for lefties. Also, the handle straps use welcro. Welcro!? Really, TOPS? Aside from these issues, the part that attaches to the handle is very floppy. All in all, the sheath serviceable, but no more. Beats a cardboard sleeve though...