Features: Angle of thread is 60 degrees. ; The crest is flat and the thread has clearance at the root allowing external thread and internal thread to engage well. ; Larger root radius and lower thread height enable easy screw thread processing and increase thread screw strength. ; The major diameter of external thread and pitch are specified by a simple numerical value (most commonly measured in millimetres). ; TAPER TAPS have a lead of eight threads and are used as a starting tap in difficult or high precision holes. ; Manufactured from HSS this general purpose tap is designed for use in medium tensile materials and is for hand or general machine use. ; INTERMEDIATE TAPS have a lead of four threads and are used in most general purpose applications to cut a thread true to a pre-drilled pilot hole. ; BOTTOMING TAPS have a lead of two threads and are used to ensure minimum thread run-out when tapping to the bottom of a blind hole. ; Bottoming Taps are typically preceded by the use of a Taper or Intermediate Tap. ; Specifications:Diameter39 mmPitch4.0 mmLeadingSetOverall Length170 mmTapping Drill35 mm