Proline Series 3/4-in x 3/4-in Threaded Adapter Fitting in the Brass Fittings department at Lowes.com
Ace 3/4 in. MHT x 1/2 in. MPT in. Brass Threaded Double Male Hose Adapter - Ace Hardware
Amazon.com : 2 Pcs 3/4 Inch Garden Hose Adapter Double Male Quick Connector with 4 Pcs Washers Double Male Connector Adapter Garden Hose Quick Connector for Connect Female Hose End to Female
M MINGLE Garden Hose Adapter, 3/4 Inch GHT to 1/2 Inch NPT, Double Male and Female Brass Connector, with Extra 8 Washers - Yahoo Shopping
Amazon.com: Fire Hydrant Hex Nipple, 2" NPT x 1-1/2" NST (NH) Male Fire Hydrant Hose Adapter Fitting Double Male Brass Fire Hydrant Connector : Patio, Lawn & Garden