Using the Milwaukee 2105P penlight is a breeze. First, insert the included AAA batteries into the penlight. You can turn it on using the on/off button or use the momentary - on button for short - term light needs. To direct the light while using both hands, you can use the protective rubber bite zone. You can attach the penlight to your pocket with the removable metal clip for easy access. When it comes to maintenance, keep it clean and dry. Since it's waterproof and dustproof, you can clean it with a damp cloth if it gets dirty. Remember, the limited lifetime warranty doesn't cover the batteries, so when the batteries run out, replace them with new AAA batteries. Don't expose the penlight to extreme impacts or harsh chemicals to ensure the lens and body stay in good condition.