Knox Box FDC Lock 2 1/2" NH/NST Male Locking Cap Hose Size (ID)_1 3/4" Hoses or an adapter

or an adapter

These gaskets are specifically for 1 1/2 inch NH A15DR60

snow plow drivers and highway maintenance personnel will be able to see and avoid damaging the hydrants

Carbon Steel 6" Raised Faced ANSI 150 Flange x 5" Storz

Knox Box FDC Lock 2 1/2" NH/NST Male Locking Cap Hose Size (ID)_1 3/4" Hoses or an adapterThe 3110 model with 2" NH threads (7. 5 TPI x 3. 068 OD) is the most widely used configuration however, thread patterns and sizes vary by jurisdiction, so always verify the correct specifications with your local fire department before ordering. Knox FDC Locks protect fire department connections (FDCs), keeping pipes clean of debris to ensure the delivery of high pressure water flow to fire sprinkler systems. The Knox FDC Lock is available in 2 1 2"