Durable 304 Stainless Steel Ball Bearings 1.5 2.5 3.5 4.5 5.556 6.5 8.5 9.525mm

Measure the bore of your bearing housing or the seat diameter in your assembly using a micrometer or caliper. The ball diameter should match the specified ball size in your bearing's datasheet. For replacement applications, refer to the original bearing part number to confirm the ball diameter. If you're designing a custom fixture, allow for appropriate clearance based on your tolerance class.

These 304 stainless steel balls are well-suited for light-to-medium load and low-to-moderate speed applications such as drawer slides, caster wheels, jigs, and hobbyist machinery. For heavy industrial loads, high-RPM spindles, or precision Grade 10 and below applications, consult a bearing specialist and verify the required hardness and grade specification against your load and speed requirements.

304 stainless steel forms a passive chromium oxide layer that resists rust in most everyday environments including moisture, mild acids, and outdoor exposure. However, it is not fully immune — prolonged exposure to chlorides (such as saltwater or bleach) can cause surface pitting over time. For marine or highly corrosive environments, 316 stainless steel is generally recommended instead.

Yes. Sizes such as 3.175mm (1/8"), 6.35mm (1/4"), 9.525mm (3/8"), and 25.4mm (1") are the metric expressions of standard fractional inch ball diameters and are dimensionally equivalent. They will fit housings and assemblies designed for those imperial sizes. Always verify with a micrometer before installation in precision assemblies.

304 stainless steel is widely used in food processing equipment and is generally considered food-safe for incidental contact. However, if your application requires certified food-grade or medical-grade components, you should request material certifications and verify compliance with the relevant standards (e.g., FDA, EU 10/2011, ISO 13485) for your specific use case. Contact us to confirm before ordering for regulated applications.

The 1pcs option is ideal for prototyping, single-unit repairs, or testing a size before committing to a larger quantity. The 500pcs pack is designed for production runs, workshop restocking, or bulk assembly work where you need a consistent supply of the same diameter. Both options ship the same ball specification — only the quantity differs.

Store balls in a dry, covered container away from direct moisture and corrosive chemicals. Avoid mixing different diameters in the same container to prevent surface scratching. For long-term storage, a light coating of machine oil or VCI (vapor corrosion inhibitor) packaging can help preserve the surface finish, especially in humid environments.