Features:*Material: Copper. High conductivity, corrosion resistance. Good electric and thermal conductivity.*It contains three hundred pieces/10 sizes of the most generally used copper pans. Great for drain plugs, water, gas and hydraulic accessories.*Comes with a plastic storage box. The copper material is for long-lasting use.*Oil sump shutter set is acceptable for all types of engines, whether or not it is vehicle engines, marine engines, generator sets, machinery and equipment.*It is very appeared for its high quality and performance. Ideal for regular maintenance and repairs. A should have in every toolbox.Specification:*Material: Copper*Quantity: 300PCs*Size type: 15*Properties: nice electric and thermal conductivity.*Dimensions: inner diameter x outer diameter x thick-ness (unit: mm)- M5x9x1 - 35 pieces- M6x10x1 - 30 pcs- M6x12x1 - 30 pcs- M8x12x1 - 30- M10x14x1 - 30 pieces- M8x14x1 - 25 pieces- M12x16x1 - 25 pcs- M14x18x1 - 25 pcs- M12x18x1.5 - 20 pcs- M16x20x1.5 - 20 pcs- M16x22x1.5 - 15 pcs- M20x26x1.5 - 15 pcsPackage Contents:300 x copper rings 1 boxNote:1. The real colour of the article may be slightly diverse from the pictures shown on web page attributable to many points similar to brightness of your video display and light brightness.2. Please allow slight guide size deviation for the data.