Set of 16 jump ring making mandrels.

These metal mandrels are 5" long.  Mandrels, except for the smallest 3 sizes, are drilled with a hole for inserting wire. Mandrel sizes are approximately 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0 & 12.0mm.

The shank diameter of the mandrels tops out at 7.0mm.  Sizes under the 7.0mm mandrels are the same diameter as the mandrel itself.