Calibrated 1 1/2“ x 11.5TPI NPT Go/No-Go Thread Ring Gauge (JBO)
Starrett 159M Screw Pitch Gage With Locking Device, 60° Threads, 0.5-11.5 mm TPI, 28 Leaves : Amazon.co.uk: Business, Industry & Science
1 x 11.5 NPT No.1 Taper Hand Tap Carbon Steel - engineeringsupplies.co.uk
Simply buy 27IR 11.5 NPT 3M IC908 Internal NPT (National Pipe Threads) Full Profile Laydown Threading Inserts for Steam, Gas and Water Pipes | Hoffmann Group
H16160EN11BSP External and Internal Carbide Thread Milling Cutter 11 TPI 1"x11 BSP Associated Production Tools
Starrett 159M Screw Pitch Gage With Locking Device, 60° Threads, 0.5-11.5 mm TPI, 28 Leaves : Amazon.co.uk: Business, Industry & Science