Blue Sea Systems 5121 Class T Fuse 400 Amp JJN Fast-Acting

The Blue Sea Systems 5121 is a 400 amp Class T fast-acting fuse designed for high-amperage DC electrical systems in marine, RV, and other mobile applications. This JJN-style fuse provides critical overcurrent protection with an extremely fast response time to prevent electrical system damage.

Key Features:

• 400 amp rating for high-current DC circuits
• Class T fast-acting design with extremely fast short-circuit response
• 20,000 Ampere Interrupt Capacity (AIC) for superior protection
• UL Listed to standard 248-15 for quality assurance
• DC tested to UL standard 198L for reliable performance in DC systems
• JJN configuration compatible with Class T fuse blocks and holders

Blue Sea Systems Class T fuses are engineered for demanding marine and mobile power applications where reliable overcurrent protection is essential. The fast-acting design quickly interrupts fault currents to protect expensive inverters, battery banks, and other critical electrical components.