LS3/5a TWEETER FELT STRIP used around KEF T27 in the LS3/5a to remove diffraction effects. Made for Falcon by original British manufacturers to full 20 Density BBC Specification. Not to be confused with inferior third party non-British manufactured grades that usually cost more. Measures 1/2" x 3/8th” and sold in 34" lengths sufficient for 2 no T27’s. Made for LS3/5a, but can also be used for controlling diffraction effects for any tweeter.