I won't be able to until this weekend. However, the picture that Cudaized posted shows a good view. The screw in the forefront of the picture adjusts the idle speed. As you screw it in, it increases the idle by pushing on the piece it makes contact with. Sorry, I don't know the technical name of what that piece is called. On my carb, the red plastic "sleeve" fits into the hole the screw goes into. It looks like on the picture posted that the hole is threaded. On mine, the hole is a lot bigger than the screw, and the sleeve fits into the hole, and the screw goes into the threaded center of the sleeve. The sleeve is pushed into the hole from the rear, allowing the larger part, or shoulder of the sleeve, to fit against the back of the carb casting. This prevents the sleeve from pulling out the front of the hole. The shoulder broke off of mine and the rest of the sleeve, with the screw still inside, slid out of the hole, since there's pressure on it from behind. If you need pics, I'll post them this weekend.