{"product_id":"electro-hardware-s1391-m10-f21-i-circuit-board-spacer","title":"Electro Hardware S1391-M10-F21-I Circuit Board Spacer","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\n\u003cp\u003eThe ELECTRO HARDWARE S1391-M10-F21-I is a round, female unthreaded circuit board spacer designed to create a fixed standoff gap between a printed circuit board and a mounting surface. Machined from Grade 2 steel with a zinc-plated finish per ASTM B633 and QQ-S-633 Type 1, this spacer provides corrosion resistance and reliable dimensional stability under service conditions. It accepts a Number 10 screw, measures 1 inch overall length, 0.194 inches inside diameter, and 0.5 inches outside diameter. Licensed electricians and electronics technicians use this fastener when mounting control boards, relay panels, or PCB assemblies in HVAC equipment, electrical enclosures, and industrial control panels.\u003c\/p\u003e\n\u003cp\u003eThis spacer is suited for residential and commercial applications where a Number 10 screw is the specified fastener and a 1-inch standoff height is required. Common install scenarios include securing circuit boards inside furnace control compartments, air handler electrical panels, and similar enclosures where board clearance and vibration isolation are required. The inch-measurement system and standard sizing make it a direct fit in typical domestic OEM and aftermarket board mounting applications.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003eFemale unthreaded round body accepts Number 10 screws for secure board mounting\u003c\/li\u003e\n  \u003cli\u003e1 inch overall length with a tight length tolerance of -0.005 to 0.005 inches\u003c\/li\u003e\n  \u003cli\u003e0.194 inches inside diameter with inside diameter tolerance of 0.000 to 0.010 inches\u003c\/li\u003e\n  \u003cli\u003e0.5 inches outside diameter for compact footprint on dense PCB layouts\u003c\/li\u003e\n  \u003cli\u003eGrade 2 steel construction with zinc-plated finish meets ASTM B633 and QQ-S-633 Type 1\u003c\/li\u003e\n  \u003cli\u003eInch measurement system; compatible with standard domestic fastener tooling\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\u003cp\u003eDesigned as an OEM-style replacement or new-installation spacer for circuit board mounting applications that specify a Number 10 screw and a 1-inch standoff height in inch-dimensioned assemblies.\u003c\/p\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cp\u003eInstallation is performed by licensed electricians or qualified electronics technicians. Always de-energize and lockout the equipment before removing or installing circuit board hardware. Use a properly sized Number 10 screw and avoid over-tightening, which can crack the PCB substrate or distort the spacer body. Follow applicable NEC requirements for work inside electrical enclosures.\u003c\/p\u003e\n\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBody Shape\u003c\/strong\u003e: Round\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eType\u003c\/strong\u003e: Female Unthreaded\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eScrew Size\u003c\/strong\u003e: Number 10\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eOverall Length\u003c\/strong\u003e: 1 inch\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eLength Tolerance\u003c\/strong\u003e: -0.005 to 0.005 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInside Diameter\u003c\/strong\u003e: 0.194 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInside Diameter Tolerance\u003c\/strong\u003e: 0.000 to 0.010 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eOutside Diameter\u003c\/strong\u003e: 0.5 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMaterial\u003c\/strong\u003e: Steel Grade 2\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFinish\u003c\/strong\u003e: Zinc-Plated\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFastener Standards\u003c\/strong\u003e: ASTM B633, QQ-S-633 Type 1\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSystem of Measurement\u003c\/strong\u003e: Inch\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePackage Quantity\u003c\/strong\u003e: 1\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eStandard Information\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: ELECTRO HARDWARE\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: S1391-M10-F21-I\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"ELECTRO HARDWARE","offers":[{"title":"Default Title","offer_id":51740146401586,"sku":"S1391-M10-F21-I","price":14.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/64ed36ec3a1c33caaf172ec4e8fe95b6_45efcc88-21d2-402e-9a8a-db03e0436a69.jpg?v=1788822882","url":"https:\/\/voomisupply.com\/products\/electro-hardware-s1391-m10-f21-i-circuit-board-spacer","provider":"Voomi Supply","version":"1.0","type":"link"}