Boss used as the coupling point for the wiper rod in the Berson Inline 50-1250 and 1500-3000 UV disinfection systems. Manufactured in PTFE for low friction and stable travel across the quartz sleeves. Inner diameter 1.5 cm, outer diameter 2.8 cm, length 7.0 cm. Resistant to chemical attack and mechanical wear. Contact us if you are unsure whether this part fits your UV system.