Use with GHE2 Boilers that require 3" venting. The kit includes: one of each 2" & 3" CPVC straight lengths, one 2"-3" CPVC bushing, one 3" 90-degree CPVC elbow, one 3" 90-degree PVC elbow, one 3" PVC coupler, one 3" to 2" coupling, and 2 vent screens.