I made this to carry a Western Digital My Passport external hard drive on a Lenovo T420 Thinkpad. The drive is about 75.3mm wide x 13.6mm. I have two openings on the bottom. One is for the USB cable, and the other is for the Activity LED.
This should fit on most modern laptops. The T420 Thinkpad has a fairly thick bezel compared to many current laptops. It's bezel is about 13.6mm thick but tapers off (see the fang like shape on the top of the laptop's lid). If your laptop's bezel isn't tapered, but is square, this holder will accommodate bezels up to 11.7mm thick.
ExtHDD_Holder.stl | 1.6MB |