These 28 mm cap chucks are stainless steel construction utilizing a compliment of pins and an elastomeric ring to hold the caps. We design our single piece or solid cap chucks to have a Delrin cover over the elastomeric ring to keep the pins in place if the ring were to fail. This cover is a necessary requirement for any bottling plant where you want to save on down time due to an unplanned chuck maintenance issue. We offer our covers in different colors, white being standard. The different colors can be used to identify different spindle positions on the machine.