Leading you to an educated decision.

Class R Fuses
High performance fuses which are rated 1/10 to 600 amps in 250 volt and 600 volt ratings.  These are all current limiting and provide a minimum of 200,000 amp interrupting rating protection. Class R and Class H fuses have the same dimensions but have a rejection feature which prevents the user from mounting a fuse of lesser capabilities (lower interrupting capacity) when used with special Class R clips.  Class R fuses will fit into either rejection or non-rejection clips.