SUITS THE STYLE OF ANY NRX COATED DRIVER This passive radiator is a good match to the SB34SWNRX-S75. Hard paper cone for improved piston operation (made in-house) with a cast aluminium chassis for optimum strength and low damping medium hardness rubber surround for improved dynamic linearity and mechanical stability. Easily adjustable moving mass for fine tuning. The disc weight (50g Included) is used to adjust the moving mass of the passive radiators. Uses an M8 bolt for mounting (see DW-50 for additional 50g weights). This passive radiator is a good match to the SB Acoustics 12" Sub-Woofer SB34SWNRX-S75 In a 2.0 to 2.5 cubic foot box this combo will get down to 30Hz, ideal for Home Theatre in a large home. Adding a plate amplifier with a low frequency boost would push the F3 even lower. Hard paper cone for improved piston operation (made in-house) Cast aluminium chassis for optimum strength Low damping medium hardness rubber surround for improved dynamic linearity and mechanical stability Easily adjustable moving mass