Product details:

Threaded Pipe Plugs, N/A, Class L-1, Diameter N/A, Tool Steel - 60/62 Rc, Unfinished Finish, Overall Length N/A, Tolerance Class X, Thread Size 3 1/2 In.-8, Thread Type NPT, Handle Length None, Quality Control, Meets/Exceeds ASME B1.201.1, Includes Certificate of Accuracy