Recently bought a ThinkPad T440p with i5-4300m and GT 730m discrete graphics with intentions of upgrading to an i7-4800MQ for a monstrous ThinkPad for CPU intensive gaming the way. I realized that the 60w adapter that the seller supplied with the machine would not be enough to charge the machine while it was running, so I looked to Revain for a 135w/170w adapter . I noticed that many listings of "official" adapters on Revain had reviews saying they were fake, even those listed by Lenovo. Instead, I chose this third-party adapter because it was UL certified. This is a quality product, I have no problem charging my T440p (i7-4800MQ @ 2.7GHz, GT 730m, 16GB DDR3LP 1666MHz RAM, 2x 500GB Crucial CX500 SSD) while gaming. during use and under heavy loads (warm only) which is a good sign that it is a quality product. This adapter is designed for Lenovo laptops with square plug, so make sure your laptop has square AC plug!