Victron MEGA Fuses are high quality, marine grade replacements ideal for use as on-board spares. MEGA fuses provide circuit protection for higher amperage applications. Victron fuses are clearly marked for easy amperage identification. The Fuse Holder is used in electrical systems in which the fuse is designed to burn out when the current exceeds the safe limit for the device being protected by the fuse. It is the end user's responsibility to determine the appropriate fuse size for the electrical circuit. In general, the fuse should be sized at approximately 1.30 times the rated power of the device being protected by the fuse.