These stands fit between the jaws as the trap is being set, thus becoming part of the trap. This holds the trap rock solid, but when fired it seperates completely. The large stand is great for setting underwater for beaver and other sets. These are the best stands for under the ice trapping money can buy. Fits 220s, 280s, and 330s. Small: 12"x5-1/4"x1". Large: 12"x7-1/4"x1-1/2".