Spark Plug Hole Rethreader Tap with 13/16" Hex Drive from 1000 /per Qty. Add to Cart This item is currently on backorder, but you can still purchase it now and we'll ship as soon as more become available. Spark Plug Hole Thread-Restoring Tap with 13/16" Hex Drive For popular 14 mm & 18 mm internal threads Length: 3", Weight: 0.31 lb MADE IN USA SKU:100