I’m not 100% sure but I believe it refers to the 2 anchor systems. The t-post hook to a wire that is anchored 4’ behind them and connected with a strap. The net has 5 clips that hook to an anchor that is a metal bar you stick in the ground at a 45 degree angle. As the pigs walk under the trap the net goes up and then back down on the anchors. It is also what prevents them from getting out. I will shoot you a pm with my # if you have any questions.

According to the website the soft ground anchors have a longer cable and a larger plate. I think it’s 24” vs 20”