Abstract: A covering that has a means for support, a means for abutment to a wall, and a means for retaining a sensing element. The covering includes a body portion and a perimeter portion with a plurality of radially extending fins. Fins with or without boss are useful for abutment to a wall or surface. One or more means for retaining positioned in the interior of the body, are useful for fixedly positioning or holding a sensing element. The covering may be position on or into a hole and optionally includes additional elements for function and use, such as reinforcing members on the radially extending fins, a central hub, and a spool position around the hub.

Abstract: A covering that has a means for support, a means for abutment to a wall, and a means for retaining a sensing element. The covering includes a body portion and a perimeter portion with a plurality of radially extending fins. Fins with or without boss are useful for abutment to a wall or surface. One or more means for retaining positioned in the interior of the body, are useful for fixedly positioning or holding a sensing element. The covering may be position on or into a hole and optionally includes additional elements for function and use, such as reinforcing members on the radially extending fins, a central hub, and a spool position around the hub.

Abstract: A fluid pressure operated piston engine assembly, such as a pump assembly, including a fluid pressure operated piston engine and a fluid valve for coupling fluid under pressure to alternative portions of the piston chamber of the piston engine. The fluid valve includes a valve spool which is translated to effect the alternative modes of coupling pressurized fluid to the piston chamber. The translation is accomplished by a shifter assembly having a shifter rod attached to the valve spool. The shifter rod includes a pair of diametrically opposed magnets attached thereto. A fork is attached to the piston engine drive shaft at one end and is mounted for limited movement along the shifter rod between the pair of magnets of the shifter rod.