APBX 10 S4S - SUB BOX SEALED 250mm 4Ohm The APBX 10 S4S sealed enclosure is the ideal choice to be driven by the new AP F8.9 bit using two channels bridged. Designed to house the single 4? Voice coil APS 10 S4S subwoofer, it offers an ultra-performing Plug & Play solution boasting all the features that make the Prima boxes unique such as the SSP (Sub Smart Plug) terminal block for a quick connection leaving no room for errors. Ultra-low profile 5.6 in. / 142 mm box with sealed design perfectly tuned to fully exploit the APS 10 D driver.