Features : 4 x double shower door rollers, 2 x upper and 2 x lower (2 lower rollers include 2 springs + 2 screws). Minimum hole in glass: greater than 12mm. Suitable for shower glass of 4-8 mm. The distance from the upper wheel opening to the top is less than 12mm No noise when opening the shower door, these glass door rollers help the shower door slide smoothly.
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