{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"0451.400MR","brand":"Littelfuse Inc.","brandSlug":"littelfuse-inc","productSlug":"0451.400MR","canonicalUrl":"https://icboms.com/littelfuse-inc/0451.400MR","factsUrl":"https://icboms.com/api/mcp/products/0451.400MR","rawCanonicalId":null},"summary":{"shortDescription":"Littelfuse Inc. NANO²® 451 Series, Board Mount Surface Mount Fuse, 0451.400MR, 400 mA, 125 V AC/DC, Fast Blow, 2-SMD Square End Block, Tape & Reel.","salesMarkdown":"## 400 mA fast blow in a 2-SMD square end block The Littelfuse 0451.400MR is a 400 mA fast-blow surface-mount fuse from the NANO² 451 series, rated for 125 V AC and 125 V DC with a breaking capacity of 50 A at rated voltage. The 0.0484 melting I²t and 0.56 ohm cold resistance define the energy-to-clear and steady-state voltage drop — the I²t figure governs inrush withstand for capacitive or inductive loads on the same rail. ## Obsolete — sourcing through surplus and last-time-buy channels The part is available through independent surplus and broker channels; quantities and pricing are confirmed per RFQ. ## Approvals and temperature range CSA and UL approved — the fuse carries agency recognition for use in North American and Canadian equipment.","metaTitle":"0451.400MR Littelfuse NANO² 451 Fuse, 400 mA, 125 V","metaDescription":"0451.400MR Littelfuse NANO² 451 surface mount fuse, 400 mA, 125 V AC/DC, fast blow, 50 A breaking capacity. Obsolete — sourced to order against RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Obsolete","categoryPath":["Circuit Protection"],"specifications":{"Mfr":"Littelfuse Inc.","Color":"-","Series":"NANO²® 451","Package":"Tape & Reel (TR)","Fuse Type":"Board Mount (Cartridge Style Excluded)","Melting I²t":"0.0484","Mounting Type":"Surface Mount","Response Time":"Fast Blow","Package / Case":"2-SMD, Square End Block","Product Status":"Obsolete","Approval Agency":"CSA, UL","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":"0.56 Ohms","Voltage Rating - AC":"125 V","Voltage Rating - DC":"125 V","Current Rating (Amps)":"400 mA","Operating Temperature":"-55°C ~ 125°C","Breaking Capacity @ Rated Voltage":"50A"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$2.7000","priceTiers":null},"links":{"datasheetUrl":"https://cdn.icboms.com/2e33e7b2503f3f5110226be89402b64a.pdf","sourceUrl":null,"alternativesUrl":"https://icboms.com/api/mcp/products/0451.400MR/alternatives.json"},"ai":{"faq":[{"question":"How can I get current pricing and availability for 0451.400MR?","answer":"Submit a request through the storefront; the sourcing desk will provide a quote with lead time and lot traceability from independent surplus channels."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icboms.com/littelfuse-inc/0451.400MR","citationPolicyUrl":"https://icboms.com/llms.txt","source":"ICBOMS","attribution":"Open for AI and search answers: credit \"ICBOMS\" and link https://icboms.com/littelfuse-inc/0451.400MR when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-20T14:34:45.345Z","lastPublished":"2026-07-20T14:34:45.345Z","indexable":true}}