Threaded studs are available in 1/4" - 20 and 3/8" - 16 thread diameter with a variety of thread and shank length for use in concrete, some types of concrete block, and A36 or A572 structural steel. They are used for applications where it may be desirable to remove the fixture, where shimming may be required of for suspending sprinkler systems. The 3/8" - 16 threaded studs have FM approval.The shank diameter for the threaded studs is 0.145" for the 1/4" - 20 diameter and 0.205" for the 3/8" - 16 diameter. Both sizes have a specially designed point to allow proper penetration into the base material. Knurled shank designs are available to increase performance in steel base materials. A plastic flute is mounted ovet the point to retain the drive pin in the fasteners guide of the tool providing guidance during the driving operation. On the 1/4" - 20 threade studs a plaster cap is also provided to protect the threads of the fastener during the driving process as well as providing guidance during installation.