Each case contains one piler and 4 of 6.5/8.5/11/13cm "C" spring clamps.
It's hard to hold miter joint glue setting by regular F clamps. Just a few "C" spring clamps you will do the work efficiently. Use the piler to expand clamps and place them on 4 corners. It looks not so strong but actually the pressure is pretty enough to hold miters firmly without marring.
