Rare Chest

Rare Chests are found throughout the Wasteland. They typically hold better loot than Common chests but also have a higher chance of getting nothing. Just like common chests, the percent shown shows the chance that it will spawn in the chest with other items.

Link to article with percents
https://docs.google.com/document/d/17BcpaAPNTUstG4mOh0ilSQ1xZok2KjhbA-TPsI1yX5o/edit