Color: Black Size: 3mm-15mm Material: Silicone Rubber Heat resistance range: high temperature 250 ° C, low temperature -40 ° C. Features: corrosion resistance, acid and alkali resistance, high temperature resistance, UV resistance, aging resistance, long service life, high and low temperature resistance, etc. How to choose the size: One size is the size of the small plug of the rubber stopper in the hole. When choosing the rubber stopper, try to choose a size that is one size larger than the actual measuring hole. This is the only way to achieve the sealing effect without falling off.
eBay