Some circuits have a number of PCB heat sources requiring cooling. For example H bridges are comprised of four FETs. Power supplies may have many LDOs, FETs and driver ICs. LED strip lights are all the rage this year.
These heatsinks will provide an off-the-shelf part for cooling multiple components on a single PCB. They will be available in different lengths. Each length features a number of receptacles.
Many PowerPegs can be attached to a single heatsink. The heatsink effectively becomes a very 'beefy' ground plane.
The heatsink serves as a 3rd PCB layer, and provides shielding.
GP43-B1, GP43-B2, GP43-B3, GP43-B4, GP43-B5, GP43-B6
This design provides a 4:1 ratio of air fin surface to PCB surface.