Vermont American 21164 18MM-1.50 High Carbon Steel Metric Spark Plug Tap
IRWIN 2459ZR Tap 18Mm-1 50 Spark Plug
Drill America DWT Series Qualtech High-Speed Steel Hand Threading Tap, Uncoated (Bright) Finish, Round with Square End Shank, Taper Chamfer, M18 x 1.5 Size (Pack of 1)
uxcell Spiral Flute HSS 1/2" Shank Twist Drill Bit 16mm for Electric Drills