High Collar Split Ring Lock Washers

High collar vs standard split ring lock washers

The difference is dimensions. A high collar washer has a smaller outer diameter than a standard split ring washer, so it fits under the narrow head of a socket head cap screw and drops neatly into a counterbored hole where a standard washer would be too wide. To make up for the reduced width, it is made thicker, which keeps its helical spring locking force. Like all split ring washers, it flattens as the fastener is torqued so the hardened ring bites the surface and resists loosening from mild vibration. Choose high collar whenever you use socket cap screws or face diameter clearance limits, and select the material for the environment and load.

Material choices for high collar split ring lock washers

• 304 stainless: corrosion resistance for wet and outdoor use.
• Metric 18-8 (A2): metric sizing, comparable to 304.
• Grade 8 yellow zinc: hardened for high-strength joints.
• Metric zinc plated: economical metric option for dry use.

Common applications for high collar split ring lock washers

• Socket head cap screw assemblies
• Counterbored holes and tight clearances
• Machinery and equipment
• Light-duty vibration resistance

For standard-width washers, see split ring lock washers, and browse every option on the main lock washers category.

High Collar Split Ring Lock Washers FAQ

Why are high collar washers used with socket cap screws?

Their smaller outer diameter fits under the narrow head of a socket head cap screw and into a counterbored hole, where a standard split ring washer would be too wide.

Why are high collar washers thicker?

The extra thickness makes up for the reduced width, keeping the helical spring locking force despite the smaller diameter.

Are high collar washers reusable?

Split lock washers are generally single-use, since flattening during installation reduces their spring tension on reuse.