SinkPAD PCB is a special type of metal core PCB( MCPCB ),
The LED sink heat pad solder direct to the metal substrate,
Also,it is called Thermal pad MCPCB,direct thermal path mcpcb.
LEDs Chip Thermal Pads solder direct to the Aluminum or Copper substrate directly,
No dielectric between LEDs heat out pads and the Metal core.
Means,thermal resistance is very small and ,
Thermal conductivity could be 235 W/m.k to 400 W/m.k.