It is a minnow trap, the kind that has an inverted cone on both ends. I cut the smooth small circle off each end so the edges were jagged. Just trapped my first rat snake or chicken snake, a 4-5 footer.
In fact, I had given up on the traps and left the eggs in there so they were really old. So snakes don't necessarily detect old eggs from new ones.
Hope this helps some of you with snake problems.