Nicro Marine 4" (102mm) Cycolac Thru-Bulkhead Hose Adaptor. Hose neatly threads to Cycolac adapter. PART NUMBER: NF 10870. Hose flange for 4" ventilation systems. Cowl ventilator. Allows 4" vent hose to be twisted into inside opening and held securely with interior "ears.".
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