The flux works for it's intended purpouse.
It is fairly easy to apply and melts to a liquid when heated, spreading the flux over the heated area.

| Advanced Quality |
Good immersion |
Neutral PH=7 +/-0.3 |
| Model no: ZJ-18 |
Smooth welding surface |
No poison, no corrosion |
| Joint high intensity |
Good insulation |
No deterioration |