1. Standard: DIN, BS, JIS, ANSI
2. Material: carbon steel
3. Size:

    1) #6: 1/2" - 3"
    2) #7: 3/4" - 3"
    3) #8: 3/4" -  4"
    4) #10: 1"- 4"

4. Thread: fine thread and coarse thread