Fuse assortment 4 Fuse assortment 4 5x20mm quick-blow with 200 fine-wire fuses 520.800. Quick-blow G fuse inserts are used to protect devices where no current surges occur when switched on or during operation, but high overcurrents or short-circuit currents must be interrupted in the shortest possible time. These inserts are often also used in mains circuits as upstream short-circuit fuses.
