This is the perfect easy open sleeve, with colored stripes as advertised. The case opens in half and the bits stand straight for easy access. Not small, can be hand-held or put in a vise for use. I have already used the .25 caliber on one of my models. I immediately bit into the plastic, didn't walk, even made round holes without the remains of burrs and excess. Every model maker needs to buy a set. In my opinion this is the best thing I have ever bought for precision drilling in small and micro plastics. I have to apologize to Daewon Industries for the feedback and comment I made earlier. The bits I used to get weren't from them, didn't have colored collars, were the same quality, and those bits didn't work well on styrenic plastic.