Packing quantity: a pair ring gauge. Please check out our store for other size. There are a variety of sizes available but they are not all listed. Level: the unified thread has six different levels, namely 1A, 3A, 2A (external thread) and 1B, 2B, 3B (internal thread). Where A and B are respectively the external and internal threads.
1A, 1B level thread is for weapons, equipment and some special requirements, which requires quick and easy assembly or thread have slight injury and stains can also assembly occasions to use this thread. 2A, 2B level threads are general purpose bolts, screws, nuts and threaded fasteners on the most commonly used standards. 3A, 3B thread for the high thread with the tightness of the lead, and half angle precision.
3A and 3B - level threads can be obtained only by means of high accuracy, effective measurement and detection. Thank you for your understanding. We strive to answer all questions and resolve any problems as quickly as possible.UNC/UNF/UNEF/UN/UNS Unified Thread Ring Gage Gauge Set Class 2A Select size T go and Z no go. Class 2A The photo is only for reference Packing quantity: a pair ring gauge Please check out our store for other size. 2A, 2B level threads are general purpose bolts, scr. This item is in the category "Home & Garden\Tools & Workshop Equipment\Hand Tools\Taps & Dies". The seller is "miss_my_car" and is located in this country: CN. This item can be shipped worldwide.