At just 14 inches square, the KEF R400b high performance subwoofer is compact, yet packs an incredible punch. Only a serious subwoofer could keep up with KEF's R-Series, and the R400b makes an awe-inspiring addition to any listening room or home theater set-up. The R Series Sale is on while supplies last. Offer available direct from KEF and from your local KEF Dealer. While supplies last.