Abstract: Systems and devices for use in working on aircraft, automobiles or other machines are disclosed. A creeper for use in working on aircraft, automobiles or other machines may include a bottom frame; a top frame; a plurality of rolling members disposed on the bottom frame; and a seat and backrest disposed on the top frame. The top frame is configured to be height adjustable, and the angle of the backrest is independently adjustable relative to the seat. A system for an adjustable seat, an adjustable backrest, and a rolling means for a mechanical creeper is also disclosed. The system includes a mechanic's creeper that comprises a bottom frame; a plurality of rolling members disposed on the bottom frame; a top frame; a seat disposed on the top frame; a backrest disposed on the top frame; and an adjustment mechanism disposed between the bottom frame and the top frame.

Abstract: A folding trailer may include a front deck and a rear deck that may be folded together into a compact configuration. The trailer may include a folding mechanism having a support base on opposing sides of the trailer. The support base may include one or more casters for supporting the trailer in a folded configuration and allowing the trailer to be easily moved. The folding mechanism may include a linkage structure which moves the support base into position when the trailer is folded and facilitate folding of the front and rear decks together.