Board Spacers, Standoffs

Part Number	Description / PDF	Quantity
24440 Keystone Electronics Corp.	HEX STANDOFF M3 ALUMINUM 5MM	20412200
971350324 Würth Elektronik Midcom	BRASS SPACER STUD METRIC THREAD	578
3015-A-256-AL RAF	5/32_ROUND_SWAGE_STANDOFFS	857
M1505-C-2545-SS-20 RAF	4.5MM RD X 8MM X M2.5 THD	2051
3049-C-632-B RAF	1/4 RD X 3/8 LENGTH	757
971070151 Würth Elektronik Midcom	HEX STANDOFF M2.5X0.45 STEEL 7MM	6922
3015T-B-256-SS RAF	5/32_ROUND_SWAGE_STANDOFFS	1000
13RS062012 Richco, Inc. (Essentra Components)	ROUND SPACER, .350 ID, .620 OD,	500
4554-632-AL-7 RAF	1/4 HEX X 1-3/4 LENGTH	420
1684-832-N RAF	1/4 RD X 1/2 LENGTH	288
13ME119 Richco, Inc. (Essentra Components)	ROUND SPACER, 13.3MM ID, 18MM OD	2000
MM-300-UC25-SL20300 Aearo Technologies, LLC – a 3M company	RND STNDFF 1/4"-20 SYN RUB 5/8"	322
13RSSR0038 Richco, Inc. (Essentra Components)	ROUND SPACER, .140 ID, .250 OD,	1000
SWI2150A Richco, Inc. (Essentra Components)	ROUND SPACER M13 NYLON 3.3MM	1851
9110-75-SS RAF	ROUND SPACER STAINLESS STEEL 1"	32
1246A-12-AL RAF	5_8-ROUND_SPACER	1672
13ME111 Richco, Inc. (Essentra Components)	ROUND SPACER, 10.4MM ID, 22MM OD	2000
1606-080-AL RAF	1/8 RD X 1/2 LENGTH	160
1801D Keystone Electronics Corp.	ROUND STANDOFF #2-56 ALUM 3/8"	0
2058-440-SS RAF	HEX STANDOFF #4-40 SS 9/16"	1274

Board Spacers, Standoffs

1. Overview

Board spacers and standoffs are specialized hardware components used to create controlled spacing between printed circuit boards (PCBs), panels, or structural elements. They provide mechanical support, electrical isolation, and thermal management in electronic assemblies. Their importance in modern technology includes enabling compact designs, reducing vibration stress, and improving heat dissipation in devices ranging from smartphones to industrial control systems.

2. Main Types & Functional Classification

Type	Functional Features	Application Examples
Cylindrical Spacers	Simple tubular design with uniform diameter	PCB layer separation in consumer electronics
Hexagonal Standoffs	6-sided structure for wrench tightening	Industrial equipment panel mounting
Self-clinching Standoffs	Permanent installation with threaded compression	Sheet metal enclosures in servers
Adjustable Spacers	Variable length through threaded adjustment	Prototype development and testing
Insulated Spacers	Non-conductive materials for electrical isolation	High-voltage power supply assemblies

3. Structure & Composition

Typical construction includes:

Material: Stainless steel (corrosion resistance), aluminum (lightweight), or nylon (insulation)
Geometry: Cylindrical (standard), stepped (for multiple board heights), or flanged (for load distribution)
Installation Features: Internal threading (male/female), knurled surfaces (for grip), or press-fit tabs
Surface Treatment: Passivation (metal), UV resistance (plastics), or EMI shielding coating

4. Key Technical Specifications

Parameter	Importance
Material Hardness (HV)	Determines wear resistance and load capacity
Thread Engagement Length	Affects vibration resistance in dynamic environments
Thermal Conductivity (W/m K)	Critical for heat dissipation in power electronics
Dielectric Strength (kV/mm)	Safety factor in high-voltage applications
Installation Torque Rating	Prevents over-tightening damage to PCBs

5. Application Fields

Primary industries include:

Electronics Manufacturing: Server racks, LED displays
Automotive: Engine control units (ECUs), ADAS systems
Aerospace: Satellite PCB mounting, avionics enclosures
Medical Devices: MRI scanner internal structures
Consumer Electronics: Smartphone PCB stacking

6. Leading Manufacturers & Products

Manufacturer	Representative Product
PEM	S-8900 Series self-clinching standoffs
RS Components	486-8826 insulated hexagonal spacers
Mouser Electronics	925206-12 adjustable PCB spacers
McMaster-Carr	91285A102 stainless steel standoffs

7. Selection Recommendations

Evaluate mechanical load requirements vs material strength
Match thread type (UNC/UNF/Metric) with assembly hardware
Consider CTE (Coefficient of Thermal Expansion) compatibility with PCB materials
Select insulated variants for >50V circuits
Use vibration-damping coatings in mobile applications

8. Industry Trends

Emerging developments include:

Miniaturization: Sub-1mm spacers for wearable devices
Material Innovation: Conductive polymer composites for EMI shielding
Smart Integration: Standoffs with embedded strain gauges for structural monitoring
Automated Installation: Self-aligning designs for robotic assembly lines
Sustainability: Biodegradable plastic options (PLA-based) entering mainstream production