I was angry at the expensive cost of batteries for my digital calipers so I made this! A simple conversion from button batteries to AAA batteries that are less expensive, you can also use rechargeable batteries that reduce your environmental impact! Update 1: Slots added to make it easier to remove battery You will Need: 1 Pen Spring 1 Triple A battery 2 four inch (10 cm) Lengths of wire (preferably 1 red, 1 black) 1 Hot Glue gun+glue or Epoxy/super glue 1 Soldering iron/ solder (I have heard of attaching wire with hot glue so this may not be necessary) Rafts: Doesn't MatterDoesn't MatterSupports: NoNoResolution: .3mm layer height (this really doesn't matter).3mm layer height (this really doesn't matter)Infill: 20% infill (Honeycomb) 20% infill (Honeycomb) Notes: 2 Perimeter shells (doesn't really matter) 3 solid top layers 3 solid bottom layers Sliced in Sli3r 1- Print the part. 2- Strip both ends of the red (positive) wire. You will need about .5 inches (~ 1 cm). 3- Solder/attach the red (positive) wire onto the positive terminal. It should be a strip of metal on either the side or the top of the old battery box (refer to the last picture) 4- Strip both ends of the black (negative wire. You will need about .5 inches (~ 1 cm) 3- Solder/attach the black wire to the negative terminal. It should be a strip of metal on the bottom of the old battery box (refer to the last picture) 4- Solder/attach the black (negative) wire to the pen spring 5- Hot glue/ attach the pen spring and the black (negative) wire to the large hole on the 3d printed part. Refer to picture 4 and 5. This will be the negative terminal. 6- Bend the stripped end of the red (positive) wire at a 90 degree angle and insert into the small hole on the 3d printed part. 7- Glue/attach the red (positive) wire on the outside of the part to the printed part. Refer to picture 3. 7- Spread the stripped portion of the red (positive) wire into a broom shape. This will achieve better contact with the positive end of the battery 8- Fold the red (positive) wire down so that it is flush with the battery box. Refer to picture 6. 9- Glue/ Attach the box to the calipers. It does not really matter where as long as the location foes not affect the functionality 10- Place the AAA battery inside the box, negative terminal to spring, positive terminal to wire 11- Take a picture! and post it here! 12- Improve on my design! I'm always looking for new ways of doing things, show me what you got! 13- Profit.