Amazon.com: Van Enterprises 1/2" PRO SERIES PVC Bulkhead Fitting Adapter For Rain Barrels, Aquariums, Water Tanks, Ponds : Pet Supplies
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Brass Bulkhead Tank Fitting 1/2" Female 3/4" Male Soild Brass Water Tank Connector Garden Straight Theaded Bulkhead Fitting Tank Hose Adapter: Amazon.com: Industrial & Scientific
1/2" Male NPT x 1/4" Female NPT Steel Bulkhead Adapter | Fastenal