304 Stainless Steel Ball Bearings Balls Industrial Metal Beads 1mm-20mm Diameter
304 Stainless Steel Ball Bearings — Precision Metal Balls for Industrial and DIY Applications When a worn bearing or undersized ball causes vibration, noise, or premature failure in a mechanism, finding the right replacement quickly matters. Engineers, maintenance technicians, hobbyists, and small-batch manufacturers who need reliable, corrosion-resistant rolling elements in a wide range of sizes rely on these 304 stainless steel ball bearings to keep equipment running smoothly. These 304 stainless steel ball bearings are available in 35 diameter options spanning 1mm to 20mm (approximately 0.039 in to 0.787 in), sold in quantities from 1 piece to 5,000 pieces per order. Each ball is manufactured from 304-grade stainless steel, offering a balance of corrosion resistance, surface hardness, and dimensional consistency suited to general industrial and mechanical use. Typical applications include replacement rolling elements in miniature and standard ball bearing assemblies, valve seats and check valves in fluid systems, load-distributing balls in linear guides and drawer slides, decorative or functional components in jewelry making and craft projects, and test or calibration balls in gauging fixtures. ⚙️ Compatibility: Suitable for use in standard ball bearing housings, valve bodies, and mechanical assemblies designed for the corresponding ball diameter. Verify bore and raceway tolerances before installation. Not rated for high-speed precision spindle applications requiring Grade 10 or finer balls. ✅ Key Features of These 304 Stainless Steel Ball Bearings 🔩304 Stainless Steel Construction Manufactured from 304-grade stainless steel, providing resistance to oxidation, moisture, and mild chemical exposure without surface coatings that can flake or wear away. 📏Wide Diameter Range: 1mm–20mm 35 diameter options in a single product listing — from 1mm (0.039 in) up to 20mm (0.787 in) — covering the most common sizes used in miniature mechanisms through medium-duty assemblies. 🔢Flexible Quantity Options Order from as few as 1 piece up to 5,000 pieces per variant, allowing both one-off repairs and production-run restocking without minimum-order friction. ⚖️Consistent Dimensional Tolerance Balls are produced to maintain diameter consistency across the batch, reducing the need to sort or measure individual pieces before assembly. 🛡️Corrosion-Resistant Surface The 304 alloy's chromium content forms a passive oxide layer that resists rust in humid environments, making these balls suitable for outdoor equipment, marine-adjacent applications, and food-adjacent machinery where mild corrosion resistance is required. 🔄Broad Application Compatibility Used as replacement rolling elements, valve balls, load-transfer media, and craft components across automotive, plumbing, electronics, and hobby sectors. 📐 Technical Specifications — Stainless Steel Ball Bearings Material 304 Stainless Steel Diameter Range 1mm – 20mm (approx. 0.039 in – 0.787 in) Available Diameters 1, 1.5, 2, 2.381, 2.5, 3, 3.175, 3.5, 3.969, 4, 4.5, 4.763, 5, 5.5, 6, 6.35, 6.5, 7, 7.144, 8, 8.5, 9, 9.5, 10, 11, 12, 12.7, 13, 14, 15, 16, 17, 18, 19, 20 mm Surface Finish Smooth, bright finish Corrosion Resistance Suitable for humid and mildly corrosive environments Quantity Options 1 – 5,000 pcs per order (see variant options) Hardness See variant options Grade / Tolerance Class See variant options Application Bearing assemblies, valve seats, linear guides, gauging, crafts Unit of Sale Per piece / per pack (see variant options) ❓ Frequently Asked Questions How do I choose the correct ball diameter for my bearing or valve? Measure the existing ball with a micrometer or digital caliper, or refer to the bearing manufacturer's datasheet for the rolling element diameter. For valve seats, the ball diameter should match the seat bore specification — typically 1.5× to 2× the port diameter for check valves. If you are replacing a worn ball, measure the seat bore and select the closest standard diameter from the available options (1mm–20mm). Are these balls strong enough for load-bearing mechanical applications? 304 stainless steel has a tensile strength of approximately 515 MPa (75,000 psi) and a hardness in the range of 70–90 HRB. This makes these balls suitable for moderate-load applications such as drawer slides, light-duty linear guides, and low-speed bearing assemblies. For high-load, high-speed precision spindle bearings, a higher-grade ball (e.g., Grade 10 chrome steel or ceramic) may be more appropriate. Contact us to confirm suitability for your specific load and speed requirements. Will these balls rust or corrode in wet or outdoor environments? 304 stainless steel forms a passive chromium oxide layer that resists rust in most humid and mildly corrosive environments, including rain exposure and freshwater contact. However, 304 is not fully resistant to chloride-rich environments (e.g., saltwater or chlorinated pools) over extended periods. For marine or high-chloride applications, 316 stainless steel balls would provide better long-term corrosion resistance. For general outdoor and indoor humid use, 304 performs reliably. Are these balls compatible with standard bearing housings and races? These balls are sized to standard metric and fractional-inch diameters (e.g., 3.175mm = 1/8 in, 4.763mm = 3/16 in, 6.35mm = 1/4 in, 7.144mm = 9/32 in, 12.7mm = 1/2 in) and are compatible with bearing housings and races designed for those dimensions. Always verify the raceway groove radius and internal clearance of your bearing before substituting balls, as tolerance class affects fit and performance. How do I decide between ordering a small quantity versus a bulk pack? For one-off repairs or prototyping, small quantities (1–10 pcs) let you verify fit and function before committing to a larger order. For production runs, maintenance kits, or resale, bulk packs (100–5,000 pcs) reduce the per-unit cost significantly. Review the price-per-piece across quantity tiers for your chosen diameter to find the most cost-effective option for your volume. Can these balls be used in food-contact or medical equipment? 304 stainless steel is widely used in food processing equipment and is generally considered food-safe for incidental contact applications. However, formal food-contact or medical-device compliance depends on the specific regulatory standard applicable to your product (e.g., FDA, EU 10/2011, ISO 13485). If your application requires certified food-grade or medical-grade materials with full traceability documentation, please contact us to confirm before ordering. 🛒 Select your Diameter and Amount above, then add to cart.