Thread Sizes

ADP Drain Plugs are available in sizes suitable for most applications.

  • British Standard
  • Unified
  • Metric
  • Fine / Course / Special
  • Parallel or Tapered

The smallest practical engine sizes are M12 or ½” and the largest size we can make is determined by your current needs. Our standard thread length is between 9 and 12 mm depending on thread diameter, but shorter or longer threads are available apon request should they be necessary. The oil sump casing thickness in combination with the sump plug diameter dictates the length of the ADP necessary to replace the current part in situ.


Replace worn, rounded plugs with realible easy to access plugs!