The shank can be either a solid cheek or a shank that can swivel (swivel cheek). It is also critical to determine what length and shape of shank is desired. Shanks are available in several styles. They may be straight, have a gentle sweep (C-bit), an acute sweep (grazing bit) or a variety of patterns (S shank, 7 shank, cavalry shank). Shank length determines the bit’s severity. The average shank length is 6 to 7 inches, but may vary from approximately 4 inches to 8-plus inches. It is important to understand certain principles about leverage bits. A straight shank, in comparison to a curved shank, is quicker acting. A longer shank produces more leverage than a shorter shank, but is slower acting. The ratio of the amount of shank above the mouthpiece to the amount of shank below the mouthpiece also helps to determine bit severity; the longer the shank is below the mouthpiece in comparison to the length of shank above the mouthpiece, the more leverage the bit will have.