Your travel trailer must be level every time you camp. Not only will you be more comfortable, but your LPG refrigerator requires it for proper operation. This great domed bullseye level is the perfect tool when you're setting up camp since it shows whether you are level in all directions simultaneously. The flange can be permanently mounted or keep it in a drawer, glove box or toolbox. And at approximately 2.5" in overall diameter, you don't have to squint to see it.