Gaugemaster GM27 Large Track Rubber (77 x 50 x 20mm)Brand: Gaugemaster Part Number: GM27 Scale / Type: Z / N / TT / HO / OO / O / Gauge 1 / G / Slot Cars An old favourite, our track rubber measures 77 x 50 x 20mm, the secret to clean track is to use a variety of cleaning methods on a regular basis. High frequency track cleaners, track cleaning pads and track rubbers work well together along with a regime of clean wheeled rolling stock.