1.  PAD value: (The present tendency PAD length does not arrest, but width request is increasingly small).
2.  Next presses the scope: Under the contact presses when the breakover best below presses 1/3 position to be approximately smallest for the breakover impedance.
3.   RT value: (R angle, circular arc angle) computing mode: R/T Otherwise cannot be smaller than 2.5 the material to be able to break (take Be-Cu 190HM as example).
4. Load capacity: Take 100~150g as good.
5. PAD size: The SMT absorption surface must retain the 1.0mm four directions good for.
6.  Arm of force question: When strength reach not easy to break the distortion. Soldering tin surface PAD: The shrapnel soldering tin surface must be smaller than PCB PAD all around size 0.1mm is good.