I have a few #0 double long springs, and have seen many over the years. But, I have never seen any advertised in the catalogs. Animal Trap Company did make and advertise a double long spring #1 trap the #11. I have talked to several trappers that said they added a spring to #0s. I believe that the #0 Victor double long spring is a trapper modification. The jaws on these traps are the same on both ends and make it easy and functional to add a spring.