TDK-Lambda ACC-PX2X1 Heatsink Kits are designed for use with PXD40 / PXD60 single- and dual-output DC-DC converters. The kits include a heatsink, mounting clips, and a thermal pad, which may already be pasted on the bottom of the heatsink, depending on the model. It is recommended to mount the heatsink to the converter before soldering the converter to the PC board. TDK-Lambda ACC-PX2X1 Heatsink Kits feature a transverse fin style and a thermal impedance of 8.3°C/W to 9.3°C/W for the HC01 kit, 7.0°C/W to 7.7°C/W for the HC02 kit, and 5.7°C/W to 6.2°C/W for the HC03 kit.