Chouinard Crack N’ Up
Chouinard Crack N Ups were early seam hooks designed to be hand placed into micro cracks. They came in sizes #1 through #6 but the number one size was extremely thin and produced in limited numbers; it is now very rare. This set is #2 through #6 with the finish being different on the #2 and #4.
Crack N Ups had angled arms which allowed a slight camming effect when the hook was weighted. The angle also helped when placing them in corners.
In the early 1990s some of my fellow desert climbers would cut one of the arms off a Crack N Up and make “Birdbeak” pitons out of them. They worked really well in blown out placements or on repeat ascents of thin seams first done with beaks or RURPs. I had a modified #6 that worked like a charm in empty bolt holes.