Rubber Tapered Plug with Hole Test Tubes Bungs Stopper for Laboratory Use Black

What is this?The Rubber Tapered Plug is great for laboratory utensils such as flasks, test tubes, or other laboratory applications, also can as a sewer plug, water pipe plug, or drain plug.What will I get?The tapered plug is in size of:33mm - 41mm : Bottom Diameter: 33mm / 1.3 inch; Top Diameter: 41mm / 1.61 inch; Height: 25mm / 0.98 inch; Hole Diameter: 5mm / 0.2 inch;37mm - 45mm: Bottom Diameter: 37mm / 1.46 inch; Top Diameter: 45mm / 1.77 inch; Height: 25mm / 0.98 inch; Hole Diameter: 5mm / 0.2 inch;48mm - 56mm: Bottom Diameter: 48mm / 1.89 inch; Top Diameter: 56mm / 2.2 inch; Height: 25mm / 0.98 inch; Hole Diameter: 5mm / 0.2 inch; In the package of: 3 x Rubber Tapered PlugAre there any advantages of the product?Made of Rubber, with good resistance to chemicals, can withstand high temperatures in a short time.

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