YOUHO Garden Hose Adapter Garden Hose to Pipe Fittings Connect, Garden Pipe Joint Extension Repair Fitting (1/2NPT(M) to 3/4 GHT(F) 2pcs)

Pretty sure for my 2771 M18 Transfer Pump, I changed one of the factory adapters to female (just to keep everything in the same direction, and to make bypassing easier). IIRC the pump housing itself is 1/2" NPT threads, typical American garden hoses are 3/4" GHT. Female swivel adapters: https://a.co/d/0eBhaSCF You want to worry the most about high flow on the suction side of the pump. I got a dedicated short hose for the intake side, 1" size. Sufficient stiffness is also important here, so the hose won't collapse under suction.