Thumbwheels allow positioning of the red dot horizontally and vertically for precise telescope alignment.
How to use:
pull out the clear plastic sheet that is at the front and on the bottom .This allows the battery to make contact so that the red dot appears when you switch it on.
Look through the hole at the front of the finder and you should see the red dot and be able to make it brighter or dimmer by using that rotary control which is also the on/off switch.
Adjust the finder so that the red dot is exactly on the object you were looking at. You can adjust it by using the two larger wheels.
You now use it by switching the finder on, then looking through the finder so that the red dot lines up on to the target you are going to observe through your telescope.
Tips:
Remember to switch it off once you have found your target to save the battery.