Atrend 12SVN-ALPINE 12" Alpine Type E / S / R / X Single Slot Vented Subwoofer Box Pro 12" Single Slot Vented Custom Subwoofer Box ALPINE SPECIFIC Dimensions 18" W x 12" H x 18.50" D Vent 1.12" W x 12" H x 14" D Tuning 37Hz1.35 Cu Ft Per Sub