This is the one and only Knex door closer. I admit it is not the best but it works fine. You can even close the door from far away by adding a string to the pin.

Step 1: The Body

This is the main part. It holds the counterweight. It is possible to make the tower 1 gray rod higher to shut the door even farther.
I Know a lot of the pictures are out of order but please try your best. If you have questions feel free to ask.

Step 2: The Counterweight

You need 2 D batteries for this. Duracell are the heaviest.

Step 3: That Other Part

It is the pulley that closes the door. To see how to set it up watch the video or look at the next step.

Step 4: Setup

It is hard to explain and I have no pictures, but I'll try my best. Place the door closer on the back side of the door near the hinges. the open part on the frame should be facing the door. the other part goes on the opposite side with a weight on it. Please watch the video and refrain from asking too many confusing questions. Mods:place this wheel to make the door close faster.