The Faithfull FAIPITCHMW Screw Pitch Gauge 52 Metric Whitworth is a handy gauge which quickly determines the pitch of various screw threads.The high-quality polished tool steel leaves are clearly marked with size and there is a locking device at both ends to securely lock the leaves. Specifications: Number of Leaves: 52.Whitworth Standard 55 Degree Threads.Metric Standard 60 Degree Threads.   Ref: UTTK9674