I thought I would post up the trap we are using on a few places. in this crude pic. the trap can be wired open along the dotted line to let the pigs come and go freely to get used to it. when you are ready to trap you untie the internal panel allowing it to contact the outside overlapping panel. the hogs will push their way in following that brown line and when they try and get back out they will push the internal panel tighter against the overlap and can not get out.