The following types of heatsinks are currently available:
The heat sinks measure 21 x 15 x 10mm and are designed for TO-220 IC packages. The package incorporates a pin for soldering down onto a PCB as well as a 3mm screw hole to secure IC's flush to the heat sink. The base to the center of the screw hole measures 17 mm.
The heat sinks measure 11 x 11 x 5.5 mm and fit a large variety of ICs. The base has a thickness of 1.33 mm and the 4 spines have a thickness of 1mm each.