A self-unloading bed includes a conveyor with chain bars that are strong, light-weight and non-damaging to the floor upon which the conveyor slides. The preferred chain bar is an elongated bar with two legs, each of said two legs having a foot. The feet extend away from the leading (unloading) direction, the transition from leg to foot being formed by smooth bends, so that no sharp edges exist that would gouge into the floor as the chain bar moves across the floor. The preferred chain bar, made of a single metal bar with four longitudinal bends, is extremely strong for its weight, and it unlikely to bend or gouge into the floor during use.