Parker - Garden Hose Fitting: 0.375″ Hose, Female Hose to Male Hose, 3/4 x 3/8″, Brass - 53578274 - MSC Industrial Supply
Amazon.com : YELUN Solid Brass Garden Hose Fittings Connectors Adapter Heavy Duty Brass Repair Male to Male, Female Faucet Leader Coupler Dual Water Hose Connector (3/4" GHT Double Male Double Female 4
Amazon.com : M MINGLE Garden Hose Adapter, 3/4 Inch GHT to 1/2 Inch NPT, Double Male and Female Brass Connector, with Extra 8 Washers : Patio, Lawn & Garden