The A4BQ Time delay Class 'L' bolted tag fuses provide superior protection for service entrance equipment. They ensure maximum protection for downstream circuit components against short circuit let-thru current. These fuses have a built-in, 4-second time-delay characteristic at 500% of the rated current. The rejection-style design prevents replacement errors. With a voltage rating of 600VAC/500VDC and a rated current of 4000A, these fuses are suitable for a wide variety of applications such as mains, feeders, large motors, lighting, heating & general loads, UPS DC links, battery disconnects, and other DC applications.