Replacement Pads for Rail Tracker™. Use with Clean TrackSolution to remove dirt and make track ready for operation. Includes 8 Cleaning Pads and 8 Finishing Pads.Works for N, OO/HO and three-rail O scale track These are replacements for those included in the Woodland Scenics WTT4550 Tidy Track kit. These are felt pads for use in completing the track cleaning task. The dark grey felt pads are moistened with a couple of drops of Clean Track Solution. Use of these will remove any oil deposits that may have accumulated on the track, as well as the grime. They are used prior to the light grey felt pads which are used to dry off the track and thus prepare it for use by the trains Ideally, they are used in conjunction with the Rail Tracker in the kit, or could be simply held against the track with your fingers and moved along the track that way. There are 2 dark grey pads plus 2 light grey pads in this pack.