Mimics the flat, triangular shaped stonefly head in tungsten. 15 heads per packet. Small are for hook sizes 12 and 14 and roughly equate to 1/8th or 3.2mm in rounds beads sizes.
Medium are for hook sizes 8 and 10 and roughly equate to 5/32nd or 4mm in rounds beads sizes.
Large are for hook sizes 4 and 6 and roughly equate to 3/16th or 4.8mm in rounds beads sizes