Quality Material: Made of soft and durable rubber, with good electrical resistance ability, the sealing rings fit these drill holes precisely and efficiently Convenient to Use: The O-rings are designed for easy installation and can fix drill holes, metal panels create a neat look on furniture and electrical boxes Usage: The rubber O-rings are used for wiring repair, etc. and can prevent metal-to-metal contact to protect wiring, cables that pass through firewalls, metal panels, etc. Features: Dimensions: The dimensions of the rubber O-rings are based on the groove inner diameter (ID) of the outer rim seam. This means that the 1" grommet has a groove width of 1" and is approximately 1.3" in outer diameter. and 1.7 cm inner diameter. Quality Rubber Material: The rubber grommets are made of quality rubber, soft and durable, they have good electrical resistance capacity. The rubber O-rings fit these drill holes precisely and efficiently. Uses: The rubber grommets are designed for easy installation and drilling holes and metal panels. Usually applied in holes in metal panels or other materials to protect cables, wires, cords from possible mechanical or chemical attack, to protect wires, cords, cables, etc. and give your furniture and electrical boxes a neat look. Multi-Purpose: Essential rubber gaskets are for cars, RV wiring work, marine uses, leaky faucets and pipe repair, etc. Good tool kit for repair shops, electricians, movers, handymen, plumbers, etc. Portable Clear Case: The 180 rubber grommets are packed in a storage case, you can carry them with you for RV trips, etc. Features: Material: Rubber. 8 Sizes: 5/8, 7/8, 1, 1/2, 7/16, 1/4, 5/16, 3/8. Quantity: 180. Color: Black. Package: 1.5cm Rubber Grommets. 5 x 2.2cm Rubber Grommets. 5 x 2.5cm Rubber Grommets cm. 20 x 0.6 cm rubber grommets. 63 x 1.2 cm rubber grommets. 40 x 6.35 mm rubber grommets. 40 x 9.5 mm rubber grommets. 101 x 0.9 cm rubber grommets. 1 snap-lock case.