Safety spring for receiver, new, long length. I cut these and they range from .38-.45 inches. Two included. Good for cutting down.

Safety spring for receiver, new, two included in long length. I cut these long length springs and they range from .38-.45 inches

Since I cut them the ends are not flattened but they are significanty cheaper than the other springs I've come across.

Some paintguns require the longer spring and some need the shorter spring (this listing is for the longer spring). I would recommend buying both a short spring and a long spring or two long springs and cutting them down.
Off the top of my head, the longer spring works well or needs to be slightly trimmed to work the best in:
in PTP benchmark automag frames,
I think Brass eagle nightmare crossman style frames
some cocker frames
nelson frames
sheridan frames