Pearl Tinsel from Veevus. Makes for great flash on fly bodies and has awesome breaking strength. Can be wrapped tightly.

VEEVUS Pearl Tinsel comes in 3 sizes:

Small: 1/64″ wide, 30m per spool.

Medium: 1/32″ wide, 20m per spool.

Large: 1/16″ wide, 11m per spool.