Pyle-Pro PH515 Constant Directivity Loudspeaker Horn (Bolt-on & Screw-on Type, 12.5'' x 7.88'') Material: ABS Glass Fiber Nominal Coverage Angle (HxV)-6 dB: 90 x 40 Cut Off Frequency: 800 Hz - Zinc Adaptor For Bolt-On To Screw-On Included Throat Diameter: 25.40mm (1'') - Bolt Circle Diameter: 58-76 mm - Dimensions: 7 7/8''H x 12 1/2''W x 10''D Mounting Flange Diameter: 76mm - Mounting Hole Diameter: 5.6mm - Mounting Holes Number: 5N Cut off frequency: 800 Hz Throat diameter 25.40mm(1") Material: ABS glass fiber