On Tuesday, Sept. 18, from 4 p.m. to close, Lunchbox Laboratory in Seattle and Bellevue will be giving away a free burger experiment with purchase of a burger.

Taking place in honor of National Cheeseburger Day, random door prizes will be given away along with prize drawings throughout the evening. Attendees who post a picture on their Facebook page while at the restaurant will also be entered to win prizes in various categories including largest burger, funniest photo and most creative photo.

Lunchbox Laboratory has two locations: Seattle (1253 Thomas Street, Seattle) and Bellevue (989 112th Avenue NE, Bellevue) and are open 7 days a week for lunch and dinner, 11 a.m. to 11 p.m.