A GSM (Grams per Square Meter) round cutter is a tool used in the paper industry to measure the grammage of paper / paperboard sample. It is a simple device that consists of a circular blade or cutter with a specified cutting area (commonly 100 cm²) and a handle. The GSM round cutter is used to cut a precise and standardized circular sample from a larger piece of paper / paperboard.

Here’s how it typically works:

1. Place the sample you want to measure on a the provided foam pad.
2. Position the GSM round cutter on the paper sample.
3. Apply downward pressure on the cutter, rotating it to cut a circular sample of 100 square centimeters (100 cm2).
4. Remove the circular paper sample.
5. Weigh the cut sample on a precision scale.
6. Calculate the GSM by multiplying the weight of the sample by 100.

The GSM cutter is a crucial tool for paper quality control and testing, as it allows manufacturers, designers, and paper experts to determine the basis weight of paper / paperboards accurately. This information is essential for ensuring the consistency and quality of paper / paperboard used in various applications.