Note: The screen presented here is from the Atari 5200 and Atari 800 versions of the game. If you are playing the game on a different system, some of the points mentioned below may not apply.
The Teleporters are advanced devices that allow Bounty Bob to immediately warp to another section of the stage. He can only use them when they are green. After entering one, push the number on the keyboard or keypad that corresponds to the teleporter you wish to go to. Bob will disappear from the teleporter he entered, and rematerialize on the desired platform. At that point, the teleporters will turn red, and be unavailable for use for a few seconds until they turn green again.
One quick strategy is to work your way up the left side of the stage, along the top, and then back down the right side. When you reach the floor again, teleport up to number 3, drop down to the left, and jump over to the number 2 platform to complete the stage.