"This Standard presents inch dimensions@ tolerances@ and sizes for straight bores@ tapered bores@ keys and keyways for unmounted industrial flexible couplings. The keys are square and rectangular keys with negative tolerances. Inspection methods for tapered bores and keyways are included in the appendices. The appendices also include the recommended design practice for tapered shafts for use with flexible couplings. Application Area. ""Standard couplings are flexible couplings pre-engineered and consistent with the individual manufacturers published catalog data."" This Standard is applicable to standard couplings as defined in AGMA Standard 510@ ""Nomenclature for Flexible Couplings."" Excluded Area. This Standard does not apply to couplings attached to shafts without keys."