TTC R8-ROT 12-Piece 1/8" to 3/4" x 16ths + 7/8" Round Collet Set with R8 Collet Rack - Perfect for CNC Milling, Lathe Work & Metalworking Projects

I have only used 4 colets so far. 2 fit perfect. One was tougher to thread into. Probably a burr on the collet thread. One was a very snug or even too snug insertion. All have held tools well. If I was in a shop where precision was my line of work, then these wouldn't work, but in a Home hobby set up they work well enough for the money. Holder is OK, but just plastic. Time will tell how this holds up.