Locate the printed bolt size to the side of the correct hole on the gauge (for example, 1/2, 3/4 or in mm for metric bolts). Locate the socket head in the socket set that has this size printed on its side. Position this socket onto the bolt head to ensure it is the correct size.
How do I know what size nut I need?
If the nut is metric, count the number of lines on the tape measure to find the measurement. If you count 9 lines, the size is a 9-mm (millimeter) nut. If the nut is US standard, count the smallest lines on the tape measure in sixteenths. Add the sixteenths together to find the size.
How are bolt sizes measured?
To measure the diameter of screws and bolts, you measure the distance from the outer thread on one side to the outer thread on the other side. This is called the major diameter and will usually be the proper size of the bolt.
What are the standard wrench sizes?
Wrenches: Standard Combination Wrenches (1/4, 5/16, 11/32, 3/8, 7/16, 1/2, 9/16, 5/8, 11/16, 3/4, 13/16, 7/8, 15/16, 1) Metric Combination Wrenches (6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19) Standard Flare Nut Wrenches (3/8, 7/16, 1/2, 9/16, 5/8, 11/16, 3/4, 7/8) Note: Each wrench may combine two sizes.
