I am very satisfied with this set. I bought this to increase the size and flexibility of my R8 collets. I found it easy to use (once I figured out the "trick" of tilting the collet to get it in and out of the nut). I get 0.001" TIR with different collets and tools. I received a 'special' collet set with two 3/16" collets and no 1/2" collet. I contacted the company and two days later had it I use a 1/2" collet. I was very pleased with their quick response times and customer service department. If you need a collet set that covers .079" to 1.024" (2mm to 26mm) with no gaps, you need to purchase a metric collet set. . Each collet has a gripping range of .039" (1mm) and there are several small gaps in the inch collet set. I'm considering getting my son an inch collet and holder. I found this set to be a great addition to my home machine shop.