Board Spacers, Standoffs

Part Number	Description / PDF	Quantity
2120-440-AL-7 RAF	HEX STANDOFF #4-40 ALUM 1-1/2"	1465
13RS039344 Richco, Inc. (Essentra Components)	ROUND SPACER, .221 ID, .394 OD,	1000
13RSSR0049 Richco, Inc. (Essentra Components)	ROUND SPACER, .192 ID, .312 OD,	975
971300485 Würth Elektronik Midcom	PLASTIC SPACER STUD METRIC THREA	536
973080365 Würth Elektronik Midcom	PLASTIC SPACER STUD METRIC INTER	313
13RS048013 Richco, Inc. (Essentra Components)	ROUND SPACER, .394 ID, .472 OD,	3000
13SP139 Richco, Inc. (Essentra Components)	ROUND SPACER, .115 ID, .313 OD,	500
13RS050018 Richco, Inc. (Essentra Components)	ROUND SPACER, .257 ID, .500 OD,	2500
13SP325 Richco, Inc. (Essentra Components)	ROUND SPACER, .140 ID, .250 OD,	988
2054-256-AL RAF	HEX STANDOFF #2-56 ALUM 5/16"	5199
970250151 Würth Elektronik Midcom	HEX SPACER M2.5X0.45 STEEL 25MM	2000
M1324-4007-B-5 RAF	6MM HEX X 31MM X M4 THD	400
M0513-3-N RAF	4.5MM RD X 14MM X 3.2MM ID	498
2101-440-AL-7 RAF	HEX STANDOFF #4-40 ALUM 5/16"	2737
SS4-10 Richco, Inc. (Essentra Components)	ROUND SPACER #4 PVC 1-1/4"	2989
2349-2520-S-12 RAF	1/2 HEX X 6.00 LENGTH	100
1535-B-6-AL RAF	ROUND SPACER ALUMINUM 3/8"	7443
13SP381 Richco, Inc. (Essentra Components)	ROUND SPACER, .140 ID, .375 OD,	2000
NAS1831A4C24 RAF	ALUMINUM 1/4 HEX FEMALE STANDOFF	125
36832MF050 Richco, Inc. (Essentra Components)	MALE FEMALE THREADED STANDOFF, #	1000

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