Features: brand new and high quality Greatly improve the accuracy, save-time and convenient for operation. Great workmanship, with strict quality control and quality assurances, high safety factors, can be used with peace of mind It is light in weight, small in size, convenient for store and manage, will not take up much space. Sutiable for 110 marble machine,C7 electric circular saw,electric angle grinder etc. made of high-quality metal materials, exquisite workmanship, very good quality and long service life. Specifications: Material: Copper+stainless steel Color: As shown Outer diameter: Approx.17mm/0.66Inch Inner diameter: Approx.12mm/0.47Inch Thickness:Approx.8mm/0.31inches Note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 10Pcs Stator Tension Spring