3/8" or 1/2" Shank Heavy Duty Spring Loaded Pull Pins /Pop Pins.
Specs:
Heavy duty spring loaded pin
1" O.D. steel pin housing with a 1-1/2" length provides plenty of surface to weld in place.
Rugged black impact resistant T handle latch is spring loaded.
Overall height/length is 3.5"
These are made from mild steel