Paper corner protectors are paper products used to protect the corners of items, and are usually used during transportation, packaging, and storage to prevent damage to the corners of items. The thickness of the paper corner protectors can vary depending on the degree of protection required and usage. Below are some common paper corner thickness ranges, but please note that exact specifications may vary by supplier and application.

1. 1.5 millimeters (mm) to 3 millimeters (mm): This is the common thickness range of paper corner protectors used for some light items and general packaging. They are suitable for some not too heavy items, such as cardboard boxes, stationery, small appliances, etc.

2. 3 millimeters (mm) to 6 millimeters (mm): This thickness range is suitable for the protection of medium-weight items. For example, some furniture, electronics and household items may use paper corner protectors from this range.

3. 6 millimeters (mm) and above: Thicker paper corner protectors are suitable for relatively heavy items. For example, appliances, mechanical equipment, and other heavy products may require thicker paper corners to provide adequate protection.

The thickness of the paper corner should be selected according to the following factors:

- Item weight: The weight of the item is one of the important factors to determine the thickness of the paper corner protector. Heavier items will require thicker paper corner guards to provide adequate support and protection.

- Shipping method: If the item needs to be transported over a long distance or may encounter greater vibration and shock, thicker paper corner protectors may be required to protect the item.

- Packaging Material: Consider what and how the item will be packaged to ensure that the paper corner protectors will fit properly with other packaging materials.

- Protection needs: Based on the fragility and value of the item, determine the level of protection required.

- Economic Factors: Thicker paper corner guards usually increase the cost. Choose between balancing protection needs and cost.