Abstract: A disposable cover includes a flexible tubular chambered body (12) with a smooth surface having an opened end (16) at the base (14) and an antenna enclosure (10) at the closed end (18). The chambered body (12) is formed of latex or rubber material having a constant diameter from opened end (16) to its closed end (18). The tubular body (12) includes an antenna enclosure (10) wherein the small chamber extends fixed thereof the closed end (18) of the body (12) thereof one side.

Abstract: A safety apparatus for a lifting structure having a crown and at least one traveling block, and an oil derrick having a crown bumper, wherein the safety apparatus comprises at least two support beams attached to crown of the lifting structure; a plate secured between the support beams; a bumper pad secured to the plate and adapted to be positioned at the crown of the lifting structure to cushion any impact with the traveling block if the traveling block is lifted towards the crown without stopping and the oil drilling rig apparatus, comprises: a derrick having a lower end for mounting on a platform, an upwardly projecting frame, and an upper, crown end; a traveling block suspended from the upper crown end within the derrick frame; drive means linked to the traveling block for driving the traveling block up and down the frame in a predetermined travel path; and a crown bumper comprising: at least two support beams attached to the derrick; a plate secured between said support beams; a bumper pad secured to the