Attachment device for an automotive creeper and mechanics chair using the same

An attachment device configured to be attached to opposed sides of an automotive creeper is disclosed herein. The attachment device includes: a first generally L-shaped member, a second generally L-shaped member, a connecting member slidably coupling the first generally L-shaped member to the second generally L-shaped member, and at one least pair of securement devices configured to respectively attach the first and second generally L-shaped members to the automotive creeper. In one or more embodiments, a width of the attachment device is selectively adjustable so as to accommodate a plurality of different automotive creepers having varying widths. An automotive creeper system and a mechanics chair using the attachment device are also disclosed herein.