Abstract: The invention is an element for spin-on filters for removing metallic fines from the medium being filtered and for neutralizing sulphuric acids therein comprises a base element having a lower recess for a magnet and an upper recess larger than the lower recess. Extender elements are stackable on the base element and an upper container within which are placed magnets spaced apart by flux spacer elements is nested in the uppermost extender element. A magnesium coil is on the exterior of the container.

Abstract: A removable threaded oil filter adaptor collar and a removable outer decorative cover for an oil filter are disclosed.

Abstract: A damper for sealing and unsealing a vertical furnace exhaust flue pipe to minimize the escape of heat when the furnace is not operating is disclosed. The damper comprises a cylindrical body adapted to form a section of vertical flue pipe having inner and outer walls. The cylindrical body has a top opening and a bottom opening and at least one transverse hinge rod horizontally transversing the body carried by opposed apertures in opposing wall portions of the body, an annular rim mounted on the inner wall of the body and a pair of oppositely extending gull-wing shaped damper shutters pivotably mounted on said hinge rod. Each of the gull-wing shaped damper shutters have upper and lower surfaces, a lower section and an outer upper section, and in the closed condition the lower sections of the shutters extend upwardly and outwardly at approximately a 45.degree. angle with the outer upper sections of the shutters extending horizontally and slightly spaced from the inner walls of the damper section.

Abstract: A safety device for tractor trailer rigs having a fifth wheel coupling arrangement comprising a trailer bed plate having a pair of oppositely situated slots and a king pin therebetween which extends downwardly into a precisely configured slot in the fifth wheel. The slots in the bed plate are curved along an arc of approximately 160.degree. on opposite sides of the trailer's bed plate about an axis extending through the king pin. The slots are of varying depth which increases towards the middle with resilient shock absorbers mounted at both ends of each slot. A pair of diametrically opposite fluid cylinders are mounted on the fifth wheel to engage the bed plate slots with a plunger element. When the brakes are actuated the pressure of the plunger elements increases against the base of the slots which in an alternate embodiment may be located together with the plunger elements at an angle to the horizontal to achieve a firm coupling.