1" BSP parallel (G1 / BSPP) (G1)
Where G1 is used, its real dimensions, and how to connect it to other standards.
G1Thread standard
DesignationG1
Major diameter33.249 mm
Threads per inch / pitch11
Thread formparallel, 55 degree
Seals onflat washer or bonded seal on the face
Used on: 1 inch pump ports, manifolds, larger irrigation fittings.
G1 drops to 11 TPI on a 33.25 mm major diameter. Do not assume a 1 inch fitting is G1: 1 inch NPT and 1 inch NH are all different threads at this size.
Quick-connect click fittings from Hozelock, Gardena and Karcher are proprietary and do not interchange. They all sit on top of a standard thread underneath, so the reliable way to move between brands is to adapt at the threaded tap or hose-end fitting, then use each brand's own connector above it.
Connect this thread
Connect to 32 mm pond hosetaildirect fitConnect 3/4" BSP parallel (G3/4 / BSPP) to 1" BSP parallel (G1 / BSPP)needs an adapter1/8" BSP parallel (G1/8 / BSPP)related standard (G1/8)1/4" BSP parallel (G1/4 / BSPP)related standard (G1/4)3/8" BSP parallel (G3/8 / BSPP)related standard (G3/8)1/2" BSP parallel (G1/2 / BSPP)related standard (G1/2)3/4" BSP parallel (G3/4 / BSPP)related standard (G3/4)1-1/4" BSP parallel (G1-1/4 / BSPP)related standard (G1-1/4)1-1/2" BSP parallel (G1-1/2 / BSPP)related standard (G1-1/2)1/4" BSP tapered (R1/4 / BSPT)related standard (R1/4)
Sources: ISO 228-1 (G / BSPP parallel pipe threads) · BSP thread dimensions chart (ISO 228 / ISO 7), AmesWeb