They work perfectly
1/8" (or 3.5mm) monaural jack on the front and a connection block on the rear. I was glad to find these because the other sites I looked at only had stereo jacks. I ran cat-5 between my family room and bedroom and terminated each end on one of these jacks. I am using this to control the TiVo in one room from the other. It works perfectly. The IR repeater I am using is a model 40430 from cables to go.