Review on 🔌 Fumei NMO to PL259 Adapter - NMO Mount Assembly with NMO and SO-239 Connectors (UHF Female) by John Arrow

Brass adapter that converts a 5/8-24 UHF thread to a 1-1/8-18 NMO adapter converts a bit messy on the 5/ side eight. Worst case it would have come loose from the threads of the UHF mount, no o-ring on the NMO adapter on the bottom. and there's no groove to add one. If you don't mind increasing your SWR by 0.5 from 1:1 to 1.5:1 and only use it outdoors, you might be fine. While 1.5 is acceptable for some, as the antenna and coax started out with a 1:1 flat ratio, it wasn't for me until this part was added. This is not the suppliers fault, but the supplier should contact the manufacturer and ask them to improve the tolerances on their brass adapters. They made the thread 5/8 to the bolt spec, not the SO-239 spec, while it's 5/8-24 UNEF. SO-239 tends to be on the smaller side of the .620 OD specs, leading to distortion.