The flagship woofer 15SSW-4HE 15” high excursion super-subwoofer from GRS, is designed to produce excellent low-frequency extension in a variety of designs. Suitable for sealed and vented enclosures, this driver is the ideal replacement or upgrade for your existing subwoofers with worn-out or blown drivers. Featuring extensive venting, dual spider design, a rubber surround capable of high-excursion, high-temperature voice coil, low Fs, and 12.3 mm of excursion the 15SSW-4HE is built for remarkable bass response on a budget.