This is the modern type thread and can be used with most modern plugs with M4 threads. I'm back on Tues.
Brass Spark Plug Cooling Fin, HT Terminal End & Thumbnut Vintage Motorcycle 3 Pc
4 Vintage Brass HT Spark Plug Terminals & 4 Thumbscrews Morris 8 Cowley Bullnose
Laser Tools 2x HT Lead Ignition Spark Testers Tool Connect HT Lead Spark Plug LL
2Pcs CR7HSA Spark Plug Replacement, Lawn Mower Spark Plug Replacement, Screw Terminal Spark Plug Replacement for NGK CR7HSA, Denso 4008/U22FSR-U 5383/IUF22, Bosch UR3AS, Champion Z9Y Copper Plus 808
2x Solid Brass Battery Terminal Connector Top Post End Clamps Set for Marine Car
High-Quality Brass Battery Terminal Clamps - 10mm M10, 2PCS Set for All Vehicles