Interrupt Speed. The AGC fuse type is a fast-acting glass tube fuse. Upon circuit overload, the fuse will almost immediately sever the power connection, protecting valuable electronics. In an area where amps fluctuate moderately, you will want to use an MDL fuse type. MDL has a slow interrupt speed, allowing for minor and short jumps in amps without causing the fuse to break. MDL fuses are available in amp ratings ranging from 1/16 to 20 amps. AGC fuses have a larger range, from 1/20 amps to 40 amps. The dimensions of the fuses are identical for the various sizes.