Each teeth is 3mm apart and the shaft is 12mm. It's the most standard format being used in China for laser machine.
The belt it fit is "3M" standard way to call in China as well. Don't get confuse with the US company "3M"
To my opinion, a mall pitch should be better used for high speed laser engraving. High pitch is usually applied for heavy and slow system. The "3M" is very popular in China for using in laser engraving machine manufacturing. The speed is running at 700~800mm/s at most.