Truma Propane Levelcheck
Whether you sell propane and propane accessories, or just prefer to taste the meat and not the heat, you'll want to grab a Truma Propane Levelcheck ($90). This handy little device uses ultrasound to check the level of the liquid gas left in your cylinder. The LED turns green if it senses liquid, and red if it senses none, so you can tell at a glance when it's time to refill. That means less time spent knocking on and shaking your propane tank, and more time spent on extracurricular activities, like enjoying a nice cold can of Alamo out back with the guys.