Grommets are versatile units that can be utilized in different industries to protect different types of units, gadgets, and devices. The main purpose of these units is to either seal a hole or protect both the cords that pass through it, as well as the device where the hole is made. As you already know, there are different types, models, and sizes of these units, and there are several standard grommet sizes. 

The size of the unit depends on several things, and you need to find the right one depending on the job at hand. The first thing you need to look for is the inside or inner diameter, or the smaller size of the hole, where your cord would pass through the unit. Note that if you are working with a solid unit, then there won’t be an inner diameter because the hole is sealed shut. You should also consider the outside diameter, and this is the part that should perfectly fit in the hole of the device where you need to install the grommet. The groove width should match the thickness of the installation wall, and the groove diameter should be as big as the hole of the installation. Know that should pay attention to the overall thickness, and even though this is not the most important part of the equation, you should find a model that will approximately match the dimensions of the unit. 

The standard grommet sizes vary depending on the exact model of the item, and they can start with a solid inside diameter, or as low as 0.2 or 1.8, whereas the outside diameter, can go be as small as 0.5 or 6. Note that the thing you need to pay attention to the most is the hole puncher, and depending on it, you can easily find the right size for your needs. The material is another important part that you need to consider, so the best thing you can do is consult with the seller on the Standard grommet sizes and the right one for you.