Crystal Bright Polishing Compound Great For Removing Scratches From Plastic Watch Crystals. This is a new Crystal Bright polishing compound. Great for removing scratches and scuffs from plastic crystals. Use by charging your buffing wheel with a small amount of compound. May also be used with a Selvyt cloth if scratches and abrasions are minor. By using in a gentle buffing motion can make old crystals look brand new. This bar is 3 oz (85 grams). It measures approximately 3 1/2" x 1 1/2" (89 x 38 mm).