This is a battery holder for an Anker Astro Mini 2600. I've been using my iPhone as a cycling computer and need a place to hold a backup battery on my bike. This holds a battery underneath the handlebar stem on my bike.Link to battery on amazon: http://amzn.com/B005X1Y7I2Not much to the assembly, all you'll need are a couple of cable ties to attach it to your bike. You may need to adjust the ID depending on the resolution of your printer. Also since your handlebar stem my be a different size the outside curve that hugs the stem may also need adjusting.