Board Spacers, Standoffs

Part Number	Description / PDF	Quantity
24333 Keystone Electronics Corp.	HEX STANDOFF M2.5X0.45 ALUM 15MM	102500
1454A Keystone Electronics Corp.	ROUND SPACER #4 BRASS 1/4"	43661500
1652-3 Keystone Electronics Corp.	ROUND STANDOFF #4-40 BRASS 1"	400500
1457C Keystone Electronics Corp.	ROUND SPACER #6 BRASS 1/2"	8271400
8402 Keystone Electronics Corp.	HEX STANDOFF #4-40 ALUMINUM 5/8"	897411400
24431 Keystone Electronics Corp.	HEX STANDOFF M3 ALUMINUM 6MM	67225400
24418 Keystone Electronics Corp.	HEX STANDOFF M4 BRASS 25MM	4611500
1921C Keystone Electronics Corp.	HEX STANDOFF #4-40 SS 3/4"	19921967
1589-2 Keystone Electronics Corp.	ROUND STANDOFF #2-56 BRASS 1/8"	452125200
4819 Keystone Electronics Corp.	HEX STANDOFF #6-32 NYLON 7/8"	2171
4832 Keystone Electronics Corp.	HEX STANDOFF #8-32 NYLON 3/4"	12105600
24473 Keystone Electronics Corp.	HEX STANDOFF M3 SS 10MM	0
8441E Keystone Electronics Corp.	HEX STANDOFF #6-32 NYLON 3/4"	15016
1547E Keystone Electronics Corp.	ROUND STANDOFF #4-40 BRASS 1"	13500
1452E Keystone Electronics Corp.	HEX STANDOFF #8-32 BRASS 1"	19
1878 Keystone Electronics Corp.	ROUND STANDOFF #4-40 BRASS 2"	35377
1621-4 Keystone Electronics Corp.	HEX STANDOFF #6-32 BRASS 1/4"	1200500
1452C Keystone Electronics Corp.	HEX STANDOFF #8-32 BRASS 5/8"	1139
24388 Keystone Electronics Corp.	HEX STNDFF M2.5X0.45 BRASS 25MM	16653100
24312 Keystone Electronics Corp.	HEX STNDFF M2.5X0.45 BRASS 25MM	11736700

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