Custom Ported Subwoofer Box Sub Enclosure for 1 12" JBL W12GTi MkII Sub ~ 32Hz | eBay
Amazon.com: JBL Single 12" Car Audio Subwoofer Sealed Enclosure : Electronics
JBL Car Audio Powered Subwoofer Enclosure - Walmart.com
GT-12BP | 12" (300mm) car audio bandpass subwoofer box
Amazon.com: JBL SUBBP12AM - 450 Watts (150W RMS) 12” Amplified 12 in. Ported Subwoofer with Sub Level Control and Distortion Free Bass with Gravity Magnet Phone Holder Bundle : Electronics