【10PK M6 X 10mm Cross Hole Nuts】 Barrel nut inner diameter: 6mm (0.236 inches), rod length 10mm (0.394 inches) x diameter 10mm (0.394 inches). These nuts are made of carbon steel, providing high hardness and durability, and can firmly secure two pieces of material together. 【Zinc Plated Finish】 The cross hole nuts are smooth and burr-free with a zinc-plated finish that effectively prevents oxidation and maximizes product longevity, adding a modern and stylish touch to your projects. 【Quality Assurance】 Made of carbon steel with excellent craftsmanship and quality assurance, the barrel nuts ensure a tight fit without gaps or wobbling after connecting the boards.