Description SharkBite Max polybutylene adapters are the fastest way to transition between polybutylene pipe and PEX, copper, CPVC, PE-RT or SDR-9 HDPE pipe in any combination. Each polybutylene transition coupling has color-coordinated collars on each end to identify which side goes with which pipe - the gray collar end is compatible with polybutylene pipe and the tan collar end is compatible with PEX, copper, CPVC, PE-RT and HDPE SDR-9 pipe. No special tools, crimping, soldering or glue required.