Metric thread andinch threadStandards
Type of units Type of pitch
metric coarse thread
metric thread
coarse
metric fine pitch thread
fine
UNC thread
inch thread
coarse
UNF thread
fine
Metric thread:Triangular screw thread. Diameter and pitch are ind
icated as mm.
60 degrees thread angle.Inch thread:Triangular screw thread. Pitch is indicated as thre
ad/inch.
Coarse thread:Combination of diameter and pitch is general and us
ed most often.
Fine thread:This thread type screw is used for special uses.