The Vermont Gage steel go (+) plug gage is a class ZZ inch gage for calibrating measuring equipment and gage parts. A certificate of accuracy traceable to NIST is available for each gage, and each pin is marked with its size and direction of tolerance in sizes over .060. Each gage is sealed in a volatile corrosion inhibitor (VCI) bag and packaged with a rust preventative. All gages measure 2 long, are within .00001 round (per ASME B89.1.5), and have at least a 10-microinch finish for a smooth finish. This gage is made of tool steel 60/62 Rc (cold stabilized) for durability and is available with either a steel or black guard finish (to inhibit corrosion and for indicating wear). Sizes are available from .0040 to 1.0005 (increments of .001), with a tolerance of +.0002 for longer wear. Plug gages are precision ground cylindrical steel plugs used to measure the diameter and depth of drilled or machined holes. They are available in different classes, based on acceptable tolerance (allowed deviation from the stated size). Standard tolerances and classes for cylindrical gages up to .825 are as follows: Class XX (.00002" or .0005 mm), Class X (.00004" or .0010 mm), Class Y (.00007" or .0018 mm), Class Z (.0001" or .0025mm), and Class ZZ (.0002" or .0050 mm). For gages with a wider diameter, tolerance gradually increases for each class. Since 1968, Vermont Precision Tools, Inc. (VPT) has been manufacturing a variety of precision round and ground pins, perforators, and special punches. Vermont Gage was formed in 1980, and manufactures a wide range of fixed limit gages. Located in Swanton, Vermont and Franklin, Kentucky, Vermont Gage manufactures 98% of the products they sell and is ISO 9001:2000 and ISO 17025 quality certified.