Features:
Made of high grade spring steel
Ground roughness is Ra0.4 Microns, plus overall fine polish
12PC by 16th: 1/8, 3/16"; 7/32", 1/4"; 5/16"; 3/8"; 7/16"; 1/2"; 9/16"; 5/8"; 11/16"; 3/4".
13PC By 32nd: 1/16, 3/32, 5/32, 9/32, 11/32, 13/32, 15/32, 17/32, 19/32, 21/32, 23/32, 25/32, 13/16
T.I.R.: 0.0003" or 5um. In order to make all collets running true, on your side, make sure your machine spindle and chuck holder running true, on my side, I'll make sure all those collets running in tenth.
Seems
like all sellers claim their collets are in 3-5 tenth, but yes or no,
only customers can tell. Copy other sellers products description is
easy, but make all collets running true is difficult. If you bought
collets with more than 2 thousands run out, don't think I'm selling the
same.
It seems like collets, tool holders and pull studs are 3 different pieces of tooling, however, when you load them to the spindle, all 3 becomes one solid piece. So make sure all 3 pieces meet certain standard, otherwise, if one piece is rough or goes bad, all others won't work right, that's why you may see large runout. Bad holders will scratch and reduce the life span and accuracy of collets. You can't use collets alone, and collets must be inside tool holders. In order to get couple tenth or half thousands total runout, both collets and tool holders must be running true by itself.
Special angled slots increase rigidity
Better overall balance of tool holder assembly
Protects tool holder from contaminants
Use
with any standard ER collet chucks for coolant-thru
tool applications.
Decent quality at reasonable price