18-in next generation high performance subwoofer, specifically designed for high SPL very low frequency applications in either a reflex, bandpass or horn loaded configuration - Walmart.com
B & C Speakers 18 in. 3400W Power Soft Woofer - Walmart.com
RE Audio XX 18 Mini Marty 11 cu ft 18 hz Subwoofer | AVS Forum
Rogue Car Audio Vandal 18 – 1200 WATT 18 inch Subwoofer – Droppin HZ Car Audio
STLF-1804-4 | 18" 450W Raw Woofer Replacement Speaker, 4" Voice Coil, 4-Ohm – Sound Town
The Procella V6 subwoofer extending below 18Hz (bass module for P28)
Sundown Audio Z-Series ZV6 18" 2500W Car Audio Subwoofer/Sub Z v.6 — Showtime Electronics
STLF-1804-8 | 18" 450W Raw Woofer Replacement Speaker, 4" Voice Coil, 8-ohm – Sound Town
Amazon.com: Seismic Audio - 18" Raw Subwoofers/Woofers/Speakers - PA DJ Pro Audio Replacement Sub - 750 Watts RMS - 240 oz Magnet - 8 Ohms - 4" Voice Coil : Musical Instruments
2 x B&C 18TBX100 18" Low Frequency 2400W Subwoofer 8-Ohms 97.0 dB 35 - 1000 Hz
Rythmik Audio • 18" servo subwoofer F18HP specs
Amazon.com: RCF L18P300 18-Inch Car and DJ Woofer, Black : Electronics
DS18 SQ82A Amplified 8" Car Audio Subwoofer with High End Aluminum Enclosure 1200 Watts