Raypak O-Ring Gasket Set (Heaters R185-405, 206-406, 207-407), is an essential component designed for Raypak's 185-405, 106-406, and 107-407 residential heaters. With a 9-1/4 inch inner diameter and 1/8 inch thickness, these gaskets perfectly fit the polymer heat exchanger. Compatible with Raypak pool heater models like the 206A, 266A, 336A, 406A Digital Atmospheric, and 207A, 267A, 337A, 407A Digital Low NOx, these gaskets ensure optimal performance. Optimize your Raypak heater maintenance with these reliable 006713F Raypak replacements. Available as a set of 2 to meet your heating needs efficiently.