MTD20N06HD N-Channel FET in a D-PAK surface mounbt package by ON Semiconductor. Download ON Semiconductor MTD20N06HD datasheet: Status: NOS (New Old Stock) supplied loose. Now a hard to source item, selling on ebay £7.39 / £6.99 (Jan 2018) Tested components : YES, individually tested both upon receipt and despatch. Top surface markings: 20N06HD OK, so we have first hand experience in using these guys.... after 3-4 years of use they tend to pry themselves away from the PCB, the back plate is supposed to act as a heat sink, but it has been found that the during pcb population, solder sometimes does create a good joint, so any electrical contact is minimal, and any heat dissapation is also compromised, add to that the fact these can run very hot and cyclic on / off switching will fracture the joint, moreover the joint will then arc, and cause an intermittent problem. Typically found on computer motherboard power circuitry. Solution: remove existing fet, clean up board pads (important) with care, flux, and re-solder in a new FET. Re-using or resoldering the original FET is simply asking for trouble a few weeks down the road. This is a very easy fix, the key is knowing to look at these fets first, (Most engineers will first replace any electrolytic capacitors, which is a fair move, then find the fault still persists). The FET may look OK, but a quick prod will often give the game away. Typical computer fault will manifest as a shutdown when extra power is required, i.e simply inserting a memory stick or floppy disc (remember those ! ). RoHS compliant: no