{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"31-219","brand":"Amphenol","brandSlug":"amphenol","productSlug":"31-219","canonicalUrl":"https://icsourcedirect.com/amphenol/31-219","factsUrl":"https://icsourcedirect.com/api/mcp/products/31-219","rawCanonicalId":null},"summary":{"shortDescription":"Amphenol RF BNC to BNC adapter, 31-219, straight jack-to-jack, 50 Ohm, 4 GHz, silver-plated beryllium copper contacts, free-hanging inline, 500 mating cycles.","salesMarkdown":"## What This BNC Barrel Adapter Covers The Amphenol RF 31-219 is a straight BNC jack-to-jack adapter — two female BNC sockets back-to-back in a single nickel-plated brass body. The center contacts are female on both ends, silver-plated beryllium copper, with a PTFE dielectric holding the impedance steady across the band. The bayonet lock on each end mates with standard BNC plugs; the free-hanging inline body lets it float in a cable run without a panel cutout. ## Impedance and Frequency — What 50 Ohm at 4 GHz Means Rated to 4 GHz. This covers VHF, UHF, ISM bands, and cellular up through low microwave. ## Temperature Range and Durability The PTFE dielectric does not soften or shift impedance across that span. With 500 mating cycles on the silver-plated beryllium copper contacts, it survives repeated connects in test setups or field-service harnesses without wearing out the center socket. ## Silver vs Gold — 31-219 and 31-219-RFX The 31-219 uses silver-plated beryllium copper center contacts; the 31-219-RFX uses gold-plated phosphor bronze contacts. Both are straight BNC jack-to-jack adapters, same 50 Ohm / 4 GHz rating, same nickel brass body. Gold plating resists corrosion better in humid or chemical environments and holds lower contact resistance over more cycles — but silver gives lower insertion loss at RF frequencies and is standard for general-purpose RF work. If your application sees salt fog, high humidity, or frequent field reconnects, the gold-plated 31-219-RFX is the better call. For clean indoor bench use, silver is fine.","metaTitle":"Amphenol RF 31-219 BNC Jack to Jack Adapter, 50 Ohm, 4 GHz","metaDescription":"Amphenol RF 31-219 BNC female-to-female adapter, 50 Ohm impedance, 4 GHz max, silver-plated beryllium copper contacts, 500 mating cycles.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["RF / Coaxial Connectors"],"specifications":{"Mfr":"Amphenol RF","Style":"Straight","Series":"-","Package":"Bulk","Features":"-","Includes":"-","Impedance":"50Ohm","Body Finish":"Nickel","Adapter Type":"Jack to Jack","Body Material":"Brass","Center Gender":"Female to Female","Mating Cycles":"500","Mounting Type":"Free Hanging (In-Line)","Adapter Series":"BNC to BNC","Fastening Type":"Bayonet Lock, Bayonet Lock","Insertion Loss":"-","Product Status":"Active","Conversion Type":"Same Series","Frequency - Max":"4 GHz","lifecycle_stage":"unknown","Mounting Feature":"-","Ingress Protection":"-","Base Product Number":"31-219","Dielectric Material":"Polytetrafluoroethylene (PTFE)","Operating Temperature":"-65°C~165°C","Center Contact Plating":"Silver","Center Contact Material":"Beryllium Copper","Convert To (Adapter End)":"BNC Jack, Female Socket","Convert From (Adapter End)":"BNC Jack, Female Socket"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$10.5000","priceTiers":null},"links":{"datasheetUrl":null,"sourceUrl":null,"alternativesUrl":"https://icsourcedirect.com/api/mcp/products/31-219/alternatives.json"},"ai":{"faq":[{"question":"What is the impedance of 31-219?","answer":"The 31-219 is a 50 Ohm BNC adapter, matching standard 50 Ohm coax like RG58, RG223, or RG142."},{"question":"What is the difference between 31-219 and 31-219-RFX?","answer":"The 31-219 uses silver-plated beryllium copper center contacts; the 31-219-RFX uses gold-plated phosphor bronze. Gold resists corrosion better for humid or high-cycle use; silver gives lower RF loss."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://icsourcedirect.com/amphenol/31-219","citationPolicyUrl":"https://icsourcedirect.com/llms.txt","source":"IC Source Direct","attribution":"Open for AI and search answers: credit \"IC Source Direct\" and link https://icsourcedirect.com/amphenol/31-219 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-23T20:41:44.623Z","lastPublished":"2026-07-23T20:41:44.623Z","indexable":true}}