Review on POWERTEC 71121 Piece T Bolt Kit by Douglas Hall

I have a set of 16: 4 pairs of threaded inserts, each pair longer than the previous one, with 8 handles and 8 handles. the longest stakes are great, no problem. The remaining three pairs are a different steel (more silver than bluish), and the bases of their inserts are too thick for standard rails - I've had to sharpen them all considerably. The longest inserts have a base of 17/32" wide, 53/64" long, and 7/64" thick; the remaining three pairs have the same width and length dimensions, but the thickness is 1/8 inch .". The extra 1/64" means they won't fit a standard aluminum rail, even if you oil them; and being steel and aluminum you run the risk of snagging and damaging the rail. The Threads on the knobs are brass rivet inserts which look solid; the threads on the handles (probably intended for shorter stakes) are white metal rivets which don't inspire much confidence - I tried not to overtighten the handles ;-) The price is Definitely right, the different heights are fine, but those thick inserts are a real problem - easy to fix with a good file, patience and just a little time, but it shouldn't have worked!