Instructions for Using THE ORIGINAL UNISEAL

  • Cut hole to the holesaw size indicated for the UNISEAL you are using. (See table below.) Example: 2" UNISEAL = 3" Hole (Holesaw).
  • A clean cut is essential to ensuring a leak free installation, we like to use a fine grit sandpaper. You only want to remove the burrs.
  • Place the UNISEAL into the hole with the flange (wide side) facing the pipe to be inserted.
  • Be sure that all burrs are removed from the pipe, a slight bevel on the end of the pipe will ease installation.
  • Lubricate the outside of the pipe to be inserted with water, soap etc , push the pipe through from the  flange side of the uniseal. The uniseal will expand in the hole as the pipe is inserted creating the seal.

    Installation Instructions

Uniseal® Pipe and Holesaw Size Table

Part No
Uniseal® Size
Sch 40 Pipe I.D.
 Pipe O.D. Size *2
 Holesaw Size

 ImperialMetric ImpMetric ImpMetric   
U0183/16"4.75mm 0.250"6mm 0.315"8mm

U0251/4"6.5mm 0.375"9.5mm 0.5"12.7mm*1
U03125/16"8mm 0.40"10.5mm 0.5"12.7mm*1
U0383/8"9.6mm 0.675"17mm 1.0"25.4mm 
U0501/2"12.7mm 0.84"21mm 1.25"31.7mm*1
U0753/4"19.2mm 1.050"27mm 1.25"31.7mm*1
U1001"25.4mm 1.315"33mm 1.75"44.4mm 
U1251 1/4"32mm 1.66"42mm 2"50.8mm 
U1501 1/2"38mm 1.9"48mm 2.5"63.5mm 
U2002"51mm 2.375"60mm 3"76.2mm 
U2752 3/4"70mm 2.913"74mm 4"101.6mm*1
U3003"76.2mm 3.5"89mm 4"101.6mm*1
U4004"102mm 4.5"114mm 5"127mm*1

U400-SDR354"102mm 4.33"110mm 5"127mm*1

*1 Note 1 - Uniseals U025 and U0312, Uniseals U050 and U075, Uniseals U275 and U300, Uniseals U400 and U400-SDR35 require the same sizes of holes. The difference is made up in the thickness of the Sarlink 4165 rubber. Uniseals with the same hole size are interchangeable, handy if you have the smaller size and want to increase the flow.

*2 Note 2 - Always measure the Outside Diameter (O.D.) of your pipe. This is the most important size to match into the Pipe O.D. hole size of the Uniseal to create your seal.

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