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LTWFITTING 3/16 in. I.D. Brass Hose Barb Splicer Fittings (10-Pack) HF39130310 - The Home Depot
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Ferrule Crimp Assortment - Kimball Midwest
SOLUSTRE 7pcs Air Hoses Air Fittings High Pressure Hose Crimp Connectors Pressure Washer Connector Plastic Hose Air Tool Fittings Crimp Fitting Crimp for Pipe Tube Hose Copper Pneumatic - Amazon.com