S-90718A220 10.5 mm ID x 21 mm OD UL 94 HB Plastic Washers

Key Features & Benefits at a Glance

• Enhanced Durability & Strength: Glass-filled nylon construction with Rockwell M111 hardness provides superior resistance to wear and deformation, extending service life in demanding industrial environments.
• Reliable Electrical Insulation: Non-conductive plastic material ensures safe isolation in electrical assemblies, preventing short circuits and enhancing component protection.
• Superior Corrosion & Chemical Resistance: Inherently resistant to rust, moisture, and many chemicals, making it ideal for harsh or humid operating conditions without degradation.
• High-Temperature Performance: Withstands continuous exposure up to 220°F, maintaining structural integrity and function in thermally challenging applications.
• Flame Retardant Safety: Complies with UL 94 HB flammability standards, reducing fire risk in electronic and industrial equipment.
• Precision Metric Sizing: 10.5mm ID and 21mm OD ensure accurate fit for M10 screws, providing consistent load distribution and secure fastening.
• Eco-Friendly & Regulatory Compliance: Meets RoHS 3 and REACH directives, supporting sustainable manufacturing and global market acceptance.

Professional Applications & Engineering Value

This M10 metric flat washer is engineered to address critical challenges in precision assemblies where metal fasteners are unsuitable. The glass-filled nylon plastic composition delivers excellent electrical insulation, eliminating risks of galvanic corrosion and current leakage in electronic components and control systems. Its low moisture absorption and corrosion resistance make it ideal for outdoor, marine, or chemically exposed settings, while the UL 94 HB certification ensures safety in applications near heat sources or electrical circuits. The washer’s ability to maintain performance at elevated temperatures up to 220°F provides reliability in automotive, appliance, and industrial machinery, where thermal cycling can compromise lesser materials. By combining lightweight design with high Rockwell M111 hardness, it reduces part weight without sacrificing durability, offering a robust alternative to metal in vibration-prone or weight-sensitive installations.

Specification Summary & Compliance

This flat washer conforms to metric dimensional standards with an inner diameter of 10.5mm and outer diameter of 21mm, designed for use with M10 screw sizes. It meets recognized industry specifications including UL 94 HB for flammability and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring adherence to restricted substance guidelines. The material hardness is rated Rockwell M111, and the washer operates effectively within a temperature range up to 220°F, supporting consistent performance under specified conditions.