The Venom Bench Preacher Curl attachment works on the REP Blackwing Bench. You have to mark on the bar that slides underneath the bench where you want to drill the pop pin hole since the REP blackwing bench is different. I used a Center Punch to mark where I wanted to drill. I also used a Titanium Step Drill Bit to drill out the hole. When my REP pop pin would fit in the hole, I knew my hole was wide enough. I did this same modification with the Venom Leg Extension / Leg Curl attachment too!