These U clips are used when you have the long spring compressed and you slide these over the spring to keep them compressed while you can either set the trap or set the other long spring if it is a double long spring. These are the same clips used on the model 3 and model 4 setters.
The small u clip is used for #2 and smaller long spring traps.
The large u clip is used more for the #3 and bigger long springs.
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