My CNC Mill came with a Coventry Quick Change Holder installed plus 1 x 6mm endmill holder and 1 x 10mm endmill holder to fit it.
Once I'd implemented Tool Offsets I had visions of a rack of tool holders with permanently fitted tools, on investigated pricing for additional holders, at £65 and upwards each that will have to wait a while, in the mean time I came up with a viable alternative for tooling up to 7mm -



The ER11 collet chuck shafts were cut down and flats cut, the 10mm shafts allow a tool to be perfectly repeatably installed in the 10mm holder with just a grubscrew, they're far more affordable at £15 or so each.

The funny looking holder with a big thread is a JT6 holder I picked up at a local tool shop, I fitted it with a Myford spindle nose, that lets me use my Myford ER25, ER32 and ER40 collet chucks  

 - Nick