Our Peristaltic Tubing Adapter Sets facilitate a secure connection between soft-walled, peristaltic tubing and more traditional, rigid-walled tubing. Through the use of a ribbed nose that fits securely inside the soft-walled tubing and a retainer sleeve that slips over the soft-walled tubing, this adapter firmly holds peristaltic tubing in place, while simultaneously allowing more permanent 1/16" OD tubing (e.g., FEP, PEEK, Stainless Steel) to be joined on the other end through the use of the Flangeless Fittings (included). These 2-pack sets allows you to make your own stoppered tubing assembly for use with some peristaltic pumps, while also minimizing the amount of soft-walled tubing that must be used in the fluid pathway. These adapters can be used with soft-walled tubing with a variety of inner diameters and outer diameters, as indicated. For Peristaltic Tubing ID (mm) - 2.55-3.80, OD (mm) - up to 6.4mm.