Most popular type & widely used type with only a small loss in effective length.

DIA LENGHT DIA LENGHT DIA LENGHT
In mm In mm In mm In mm In mm In mm
1.5 9.3 2.5 13.8 3.175 25.4
1.5 9.8 2.5 15.8 3.2 19.3
1.5 11.8 2.5 19.8 3.5 15.8
1.5 13.8 2.5 23.8 3.5 34.8
1.811 13.46 2.5 25.8 3.967 19.05
2 7.8 2.778 11.17 4 15.8
2 9.8 3 9.8 4 25.4
2 11.8 3 13.8 4.755 25.4
2 13.8 3 15.8 5 23.8
2 15.8 3 17.8 5 29.8
2.381 10.57 3 18.4 5.542 19.05
2.381 19.8 3 19.8 6 30
2.381 12.55 3 21.8 6.5 30.8
2.381 16.85 3 23.8 7 30
2.5 9.8 3 29.8 7.25 25
2.5 11.8 3.175 19.05 7.5 19