AD 56505750 11" Pad Driver Assembly for Nilfisk Advance Scrubbers. Short trim poly bristles in conjunction with a center locking floor pad holder, securely hold your floor pad to the pad driver. Filament is set in an 11" diameter solid heavy duty plastic molded block. Includes 3 mounting drive lugs. Fits Nilfisk Advance scrubbers including Adgressor 3520 (with 35" disc scrub deck), 600S, BR 950S, 1700, 2067, Convertamatic 24D, X24D, 240, HydroRetriever 240, Trac 240, 240HD, 240LX, 240HR, and 4500 These brushes have a 5-1/2" center hole. Many machines require 2, or in some cases, 3 or 4 brushes. Please check your machine before ordering. Often listed as 12". Replaces Nilfisk-Advance 56505750, 505750. Our Part Number AD 56505750