Color: grey shower door rollers; Model: double shower door rollers. diameter of rollers: 23 mm; Width: 5mm. Minimum hole size in glass: 11 mm. Suitable for glass thicknesses of sliding doors from 3 to 6mm. Material: plastic, BS nylon and stainless steel shower door rollers. These single shower door rollers fit glass shower doors when the distance from the center of the hole to the edge of the glass is 18 mm. li> The package includes: 4 Shower Roller Doors at the top Functions: -Easy adjustment of the height and angle of the door. < Br> -These shower door rollers can be used in quadrants, arched showers or straight sliding doors. -The shower door roller is adjustable, easy to install and the shower door is smoother than before, do not shake or scream! Br> -You do not have to fish in cabins and plumbers or buy new shower doors. Br> -The kit includes 4-top adjustable shower door rollers and 4-bottom shower door rollers. < Br> -Supplied with screw cap. < Br> -The spring is also suitable