Rubber Seals (Connector Seals) Picture Diagram Part # Dimensions A (Hole Saw Size) Dimension B (Pipe Size) Dimension C Material Master Seals XPS 680 45mm 25mm 20mm NBR XPS 670 51mm 32mm 20mm NBR XPS 660 65mm 50mm 20mm NBR XPS 650 76mm 65mm 20mm NBR XPS 640 89mm 80mm 20mm NBR XPS 630 98mm 90mm 20mm NBR XPS 620 121mm 100mm 20mm NBR XPS 610 168mm 150mm 20mm NBR Star Seals RSR C40 4″ 3″ 6mm NBR RSR C20 5″ 4″ 10mm NBR RSR C30 5″ 4″ 5mm NBR RIR 310 5″ 4″ 4mm NBR RSR C10 7″ 6″ 10mm NBR Rubber Seals (Connector Seals) XRS 510 5″ 4″ 15mm NBR XRS 520 5″ 4″ 26mm NBR RRG 710 5″ 4″ 13mm NBR XRS 720 5″ 4″ 38mm NBR XRS 310 5″ 4″ 16mm NBR Envelope Seals RRE 320 2-1/2″ 2″ 24mm NBR RRE 330 3-1/2″ 3″ 34mm NBR RRE 340 4-1/2 4″ 38mm NBR