SMD fuse for board-level overcurrent protection
The Littelfuse 0451010.MRL is a 10 A fast-blow surface-mount fuse from the NANO²® 451 series, housed in a 2-SMD square end block package measuring 6.10 mm x 2.69 mm x 2.69 mm. Rated for 125 V AC or DC, it clears overcurrents with a breaking capacity of 35 A on AC circuits and 50 A on DC circuits — the DC rating is the tighter constraint for fault clearing in a 125 V DC rail. The 0.0056-ohm cold resistance and 26.46 melting I²t mean the fuse handles moderate inrush without nuisance opening; the I²t value is the one to check against your load's surge profile during start-up or capacitor charging.
Regulatory approvals and sourcing posture
CSA, PSE, and UL approved — the UL listing covers the 125 V AC/DC ratings, so the fuse is accepted in North American and Japanese equipment without additional agency review.