M10 Internal Locking Washer M10 zinc plated mild steel locking washer. If you really want to make sure your jacks aren't coming loose, these are for you. Outside Diameter: 17mm Inside Diameter: 10 mm Thickness: approx 1mm Product Code: M10lock Product Condition: New Notify me when product is back in stock £0.24 inc. tax £0.20 ex. tax ? Tax based on United Kingdom. x