Truglo Centra peep Pro-Series 3/16 sight, black the Truglo Centra peep Pro Series is a lightweight machined aluminum design. The angled design allows for perfect peep alignment. The 3/16″ aperture diameter does not require tubing. Features:- lightweight aluminum construction – precision cnc-machined – angled design for shorter axle-to-axle bows – aperture diameter is 3/16″””