Construction:Bellows+Interlock+Out braid. This series of professional quality flexible exhaust connector pipes is intended for weld-in installation in an exhaust system to isolate noise, relieve vibration, and reduce the stress on the pipes.a stainless steel internal bellows for vibration isolation, internal stainless steel braid to reduce noise and/or whistling, and an externalstainless steel braid for protection of the bellows.
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