{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"0451008.MRSN","brand":"Littelfuse Inc.","brandSlug":"littelfuse-inc","productSlug":"0451008.MRSN","canonicalUrl":"https://icboms.com/littelfuse-inc/0451008.MRSN","factsUrl":"https://icboms.com/api/mcp/products/0451008.MRSN","rawCanonicalId":null},"summary":{"shortDescription":"Littelfuse Inc. NANO²® 451 series, 0451008.MRSN, Board Mount SMD Fuse, 8 A, 125 V AC/DC, Fast Blow, 2-SMD Square End Block package.","salesMarkdown":"## SMD fuse for 125 V board-level protection The Littelfuse 0451008.MRSN is an 8 A fast-blow SMD fuse from the NANO²® 451 series, rated for 125 V AC and DC circuits with a breaking capacity of 50 A at rated voltage. Housed in a 2-SMD square end block package measuring 6.10 mm x 2.69 mm x 2.69 mm, it mounts directly to the PCB surface — no through-hole or cartridge-style body. ## Current, voltage, and let-through energy Rated 8 A continuous with a cold DC resistance of 0.0077 ohms — the voltage drop at rated current is under 62 mV, negligible for most 125 V rails. The melting I²t of 20.23 A²s defines the energy needed to open the element; this figure is used to coordinate with downstream semiconductor protection and to size the trace width on the PCB. ## Approvals and compliance Carries CSA, METI, and UR approvals — accepted in North American and Japanese equipment without additional agency review.","metaTitle":"Littelfuse 0451008.MRSN NANO² 451 SMD Fuse, 8 A, 125 V","metaDescription":"Littelfuse 0451008.MRSN NANO²® 451 SMD fuse, 8 A, 125 V AC/DC, fast blow, 50 A breaking capacity. Active production. Sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Circuit Protection"],"specifications":{"Mfr":"Littelfuse Inc.","Color":"-","Series":"NANO²® 451","Package":"Tape & Reel (TR); Cut Tape (CT)","Fuse Type":"Board Mount (Cartridge Style Excluded)","Melting I²t":"20.23","Mounting Type":"Surface Mount","Response Time":"Fast Blow","Package / Case":"2-SMD, Square End Block","Product Status":"Active","Approval Agency":"CSA, METI, UR","lifecycle_stage":"unknown","Size / Dimension":"0.240\\\" L x 0.106\\\" W x 0.106\\\" H (6.10mm x 2.69mm x 2.69mm)","DC Cold Resistance":"0.0077 Ohms","Voltage Rating - AC":"125 V","Voltage Rating - DC":"125 V","Current Rating (Amps)":"8 A","Operating Temperature":"-55°C~125°C","Breaking Capacity @ Rated Voltage":"50A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$1.2200","stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/604a0e4c498aa97d2607992508357d04.pdf","sourceUrl":null},"ai":{"faq":[{"question":"What is the breaking capacity of 0451008.MRSN?","answer":"50 A at the rated 125 V AC or DC — sufficient for secondary-side protection in power supplies and control circuits where the prospective fault current stays below that level."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/littelfuse-inc/0451008.MRSN","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/littelfuse-inc/0451008.MRSN when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-08-11T15:49:49.435Z","lastPublished":"2026-08-11T15:49:49.435Z","indexable":true}}