1st Generation: JIS B 1122 class 2

Suitable for thin plate and plastic fastening as per JIS B 1122 appendix.
Widely distributed as a standard tapping screw. Average performance.

2nd Generation: B-type

Advanced form of JIS B 1122 Class 2, with trilobular thread, same thread angle (60 degree) and pitch.
Tightening Torque is lower than 1st generation according to torque analysis result.
Suitable for thin plate and plastic fastening.

3rd Generation: P-type

Double threaded with 45° thread angle, wider thread compared with B-type and trilobular thread.
Fastening speed is high due to double thread but it also means loosing quickly.
TF* point and TD* point higher, so we have to pay attention to F/D ratio.
Using repeatedly on the same pilot hole is not recommended.

TD:Torque of Driving
>>>Min. Torque for fastening

TF:Torque of Failure
>>>Torque for breaking counter material.It includes idling and cracking.

TS:Torque of Setting
>>>Best Torque of Setting

4th Generation: non-sert®

Single threaded same as 1st and 2nd Generation but difference is 30 degree thread angle, trilobular thread and large pitch.
Lowest TD in all generations.
Low stress against the mating material. TF is lower than 3rd Generation, but mostly F/D ratio indicate higher, these results conclude that using non-sert® is safe and best for plastic fastening. Above all, non-sert® is the best screw for repeat use on the same pilot hole.