Check the listing for details. Irritec FHT End Cap Flush Valve. Condition: New. Listed at 7.13 USD. Garden Hose Threads (GHT, FHT, MHT) are unique in that they make the water-tight seal with a flexible washer between the two connection pieces. Thread seal tape is not recommended since it can inhibit the full threading together of the pieces, thus not allowing a tight leak-proof seal. GHT are not compatible with NPT or IPT/IPS fittings commonly found in iron pipe or PVC water systems. Use this flush valve cap to turn the Perma-Loc end caps into a flush valve. Simply remove the standard cap and replace with this flush valve. This item has standard 3/4" female hose thread connection. This low pressure valve allows water to flush out at system start-up with as little as 0.66 GPM (39.6 GPH) flow required to close the valve. The valve opens at shutdown when system reaches 0.87 PSI.