POWERTEC 70153   Angled Dust Port, 4-Inch Designed to attach easily and securely to machine's chip chute for connecting to dust collection systems Pre-drilled mounting holes for easy attachment Tough, durable ABS plastic material Flange measures 7-1/2-Inch by 4-1/4-Inch 4-Inch nominal end measures 3-61/64-Inch O.D. And 3-5/8-Inch I.D.