DS18 PRO-HA102 Bolt On 2" 35° 4.84" Depth Aluminum Horn All aluminum casing with brushed DS18 logo. This throat will require a 4 bolt pattern on your driver to attach correctly. Now you can save some space while having crazy loud directional sound from your drivers. Highlights Aluminum frame with brushed DS18 logo 4 bolt pattern for compatibility for most bolt on drivers Installation Type: Bolt-on Throat Diameter: 2" / 50.8mm Nominal Horn Diameter: 6.5" Sound Coverage: 35° Rounded Technical Deta