Basic Piston Door

I found this while experimenting with pistons

Step 1: You Will Need:

2 sticky pistons, 1 lever, 4 blocks of choice (not obsidian) and a redstone torch

Step 2: Pistons and Blocks

Place the blocks and pistons as shown in the picture

Step 3: Add the Redstone Torch and Lever

Add the redstone torch and lever as shown

Step 4: Lever Usage

The door will open and close upon hitting the lever