ER32 x 18PCS 1mm shrinkage
3-2,4-3,5-4,6-5,7-6,8-7,9-8,10-9,11-10,12-11,13-12,14-13,15-14,16-15,17-16,18-17,19-18,20-19mm


eg.

6-7mm will hold 6mm and 1/4"
9-10mm will hold 10mm and 3/8"
12-13mm will hold 12mm and 1/2"
15-16mm will hold 16mm and 5/8"
19-20mm will hold 20mm and 3/4"


Tim