99-06 GMC Sierra Ext Cab Custom Dual 12" Chevy Sub Box + 2× Harmony HA-F124 Subs, Kicker CX600.1 Amp & HA-AK8 8GA Kit

Package contents: 1 x Chevy Subwoofer Box (Custom Dual 12" for 99-06 Ext Cab), 2 x Harmony Audio HA-F124 Flatline Series 12" (single 4 ohm), 1 x Kicker CX600.1 Class D Sub Amp, 1 x Harmony Audio HA-AK8 Car 8 Gauge 900 Watt Amp Kit - Nickel Finish. Chevy Custom Dual 12" Sub Box (fits 99-06 Ext Cab): Designed to sit under the rear seat and fire downward. Sealed enclosure with an internal air space of 0.95 Cubic Feet and a mounting depth of 5-3/4". Overall enclosure dimensions: Width 51" x Front Height 9-3/4" x Rear Height 7-1/4" x Depth 13-1/2". Harmony Audio HA-F124 Flatline Series 12" (x2): 12" Flatline Series car subwoofer. Power handling — Peak: 800 watts; RMS: 400 watts. Sensitivity: 87.3 dB. Frequency response: 25Hz-1.2Hz. Mounting depth: 4 1/2". Mounting cutout diameter: 11 1/8". Single 4 Ohm. Kicker CX600.1 Car Audio Class D 1200W Sub Amp: RMS power: 300 watts x 1 @ 4 ohms, 600 watts x 1 @ 2 ohms. Maximum power output: 1200 watts x 1. Variable bass boost (0 to +12 dB at 40 Hz). Input sensitivity: Low level 125mV-5V; High level 250mV-10V. Frequency response: 25-200 Hz. Dimensions: 7-3/16" W x 8-1/8" D x 2-3/8" H. Harmony Audio HA-AK8 Amp Kit: 8 gauge amp wiring kit rated 900 Watt, nickel finish. This bundle provides a ready-to-install solution for 99-06 GMC Sierra extended cab trucks: a custom dual-12" sealed box built for under-seat installation, two Harmony HA-F124 subs, a compact Kicker CX600.1 power amp, plus the HA-AK8 8GA installation kit.