Attachable Heat Sink for TO 220, 21 and 25 K/WAll attachable heatsinks are made from black anodised diecast aluminium.Heatsinks in the FK 237 Series have the following features:A very slim design ensures that it does not require much spaceEasy assembly by sliding the heatsink onto the TO220 housingOptimal heat transfer as the fastening clips on the TO 220 housing press firmly on the heatsinkEffective heat dissipation in both horizontal and vertical installation positionsVersions:FK 220-SA-220No solder tags, with a transistor retaining spring for simple attachment to the TO 220 housingFK 237-SA-220 HWith tin-plated solder tags, enabling it to be soldered directly onto the printed circuit board in a horizontal positionFK 237-SA-220 ONo solder tagsFK 237-SA-220VWith tin-plated solder tags, enabling it to be soldered directly onto the printed circuit board in a vertical position