Abstract: A wrist compass is formed with a base member having straps at each side for strapping to a user's wrist and with a detachable compass body having complementary interengaging surfaces for removably securing the compass body to the base member. The base member also is provided with folding lens and sight line elements to overlie the attached compass face in a folded position and to be erected to a sighting position when desired. The lens and sight line elements are preferably formed entirely of transparent material so that the compass face is visible when the elements are folded thereover.

Abstract: A pin tumbler cylinder lock having a plug eccentrically positioned within a cylindrical bore of a housing. Surrounding the plug are longitudinally aligned sleeve segments that together therewith form a composite plug unit that can be rotated in the housing bore by a proper key. Formed on the outer surface of each sleeve segment coincident with pinways therein are recesses that are spaced from the recesses in adjacent sleeve segments. Additional internal recesses are formed in the inner surface of at least one of the sleeve segments closely adjacent a pinway extending therethrough. The internal recesses receive the tumbler pin when it is forced upwardly simultaneously with the application of torque on the plug. In one embodiment, the internal recess is a single recess coincident with the pinway and extending circumferentially therefrom. In another embodiment, the internal recess comprises a pair of recesses located on opposite sides of the pinway and spaced circumferentially therefrom.

Abstract: A cylinder lock comprising a plug, with an eccentric face, a cylinder and an eccentric sleeve between the plug and cylinder. When a proper key is inserted and raises the pins to operating shear level the plug and sleeve can be turned as a unit on an axis to unlock or lock, but in the event there is a single pin restraining the rotary motion of the sleeve, only a limited plug motion is permitted as it is now in an eccentric relation with respect to the cylinder. Picking of the lock is prevented by dividing the sleeve into segments rotatable with respect to each other and providing each with circumferentially extending recesses in which tumbler pins can become ledged.

Abstract: A pin tumbler cylinder lock having a plug eccentrically positioned within a cylindrical bore of a housing. Surrounding the plug are longitudinally aligned sleeve segments that together therewith form a composite plug unit that can be rotated in the housing bore by a proper key. Formed on the outer surface of each sleeve segment coincident with pinways therein are recesses that are spaced from the recesses in adjacent sleeve segments. The bottoms of the recesses form false shear levels that hinder picking operations while the side walls thereof form pin obstructions that prevent forcible axial removal of the plug and sleeve unit from the cylindrical housing. Additional security is provided between the plug and at least one sleeve segment by a mechanical coupling that prevents relative axial motion therebetween. The coupling prevents axial removal of the plug.