10 Pcs 10mm Diameter Stainless Steel Serrated Hex Flange Nuts Locknuts M4x0.7mmCategory: 10 Flanged Stainless SteelFeatures: 0.7mm pitch, 4mm height, 10mm diameter, M4 hexagon flange nuts.A flange nut is a nut that has a wide flange at one end that acts as an integrated, non-spinning washer. This serves to distribute the pressure of the nut over the part being secured, reducing the chance of to the part and making it less likely to loosen as a result of an uneven fastening surface.The flange may be serrated to provide a locking action. The serrations are angled such that they keep the nut from rotating in the direction that would loosen the nut. Because of the serrations they cannot be used with a washer or on surfaces that cannot be scratched. The serrations help in avoiding vibration of nut and increase the holding power of nut.For CALIFORNIA residents only: WARNING: This product contains chemicals including DEHP, which is known to the State of California to cause cancer and birth defects or other reproductive harm.Please note that by posting this Proposition 65 warning, we are notifying you that one or more of the Proposition 65 listed chemicals may be present in a product. With Unique Bargains' products, the exposure to these chemicals may be of no significant risk to you, but out of caution, we have elected to place this warning on our site to make sure our customers are informed.You can find more infomation at http://www.oehha.ca.gov/proposition-65/about-proposition-65.