Thru Hull Exhaust Flappers - w/Flapper, Black
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CENTEKThru Hull Exhaust Flappers - w/Flapper, Black

Prices from $107.99 - To $137.99


In stock online.
Model # 3683174 | Mfg # 1200299UPC # 808880120470


Product Overview

A great way to reduce risk of backflow in 3in. and 4 in. exhaust systems.

Exhaust flappers are an effective way to protect the engine from water that surges back into the exhaust system. Centek thru-hull flappers are constructed of a compression molded fiberglass to eliminate corrosion issues and feature a 7/8" wide flange to provide more than adequate bedding surface for installations close to the waterline. A weighted rubber flap allows exhaust and cooling water to escape freely and closes off to the back-flow of sea water. The combination of rubber flap and fiberglass thru-hull makes operation silent. Available for 3" and 4" exhaust systems.

Key Features

  • Fiberglass thru-hull construction is non-corrosive
  • Weighted rubber flaps repel back flow surges caused by waves, following seas or backing down
  • Wide mounting flange provides extra surface for bedding material; ideal for installations close to the waterline
  • Class 1 fire retardant resin to stand up to heat and prevent the spread of fire
  • Available for 3" and 4" exhaust systems
  • Replacement flap kits are available


  • Hose Size: 3", 4"
  • Dimensions 3": 4 7/8" dia flange (3" hose) x 5 1/2"L (3" from flange inboard)
  • Dimensions 4": 5" dia flange (4" hose) x 7 3/4"L (4 1/2" from flange inboard)
  • Approvals: ISO 9001:2008, Lloyd’s Register, ANAB, UL94V-0 flame retardancy

Data Sheet 3"

Data Sheet 4"


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