Mercury 5x20mm Fast Blow Fuse Assortment - 160 Pack (0.5A-10A)

The Mercury fast blow fuse assortment contains 160 glass 5x20mm fuses across eight current ratings, from 0.5A to 10A. Each rating includes 20 individual fuses, stored in a compartmentalised plastic case with clear labelling for each amperage. The fuses are quick-blow (F-rated) types, meaning they respond rapidly to overcurrent conditions and protect sensitive electronics from sustained overload.

Designed for electronics repair workshops, service benches, AV installation technicians and general electrical maintenance, the assortment covers the most common fuse ratings needed for amplifiers, mixers, power supplies, lighting controllers and consumer electronics. The 5x20mm dimension is a global standard for cartridge fuses, fitting most fuse holders rated for 250V AC applications. Having all eight ratings in one case reduces the need to stock individual packs and allows technicians to match the correct fuse to the equipment without ordering delays.

Each fuse is a glass-bodied cartridge with nickel-plated end caps and a visible internal element, allowing visual inspection for blown elements before testing. The plastic storage case measures approximately 180x100x25mm and features a hinged lid with snap closures, keeping fuses organised and protected from workshop debris. The compartments are labelled with the amperage rating, so technicians can identify and replace stock quickly during high-volume repair work.

What does fast blow mean?

Fast blow (F-rated) fuses respond quickly to overcurrent conditions, typically within milliseconds. They protect sensitive electronics and components that cannot tolerate even brief overloads. This contrasts with time-delay (T-rated) fuses, which tolerate short current surges such as motor start-up inrush.

Are these suitable for mains voltage equipment?

Yes. The fuses are rated for 250V AC, which covers UK mains voltage (230V) and most international mains applications up to 240V. Always match the fuse current rating to the equipment manufacturer's specification shown on the equipment's rating plate or in the service manual.

What equipment uses 5x20mm fuses?

Common applications include audio amplifiers, mixing desks, PA systems, lighting controllers, bench power supplies, computer peripherals, set-top boxes, AV receivers and general consumer electronics. The 5x20mm size is an international standard dimension for low-power equipment fuses.

Can I use these to replace ceramic fuses?

Only if the equipment specifies glass fuses or allows either glass or ceramic types. Some high-rupture-capacity (HRC) applications require ceramic-bodied fuses. Check the equipment service documentation or the markings on the original fuse before substituting.