Hairpin Lace is a CROCHET technique done
using a crochet hook and a hairpin lace loom.
The
loom, which consists of two parallel metal rods
held at the top and the bottom by removable
bars.
Years ago, the ladies used a metal U-shaped
Hairpin to do the looming.
Tutorial: Basic Hairpin Lace Strip.
http://hookandneedledesigns.com/FreePatterns/BasicHairpinLaceStrip.pdf