Abstract: A cylindrical combination lock body is associated with a flexible shackle, both ends of which are connected to a single end of the lock body so that the body and shackle are fitted within an approximately constant diameter. A cylindrical sleeve is sized to telescope over the shackle and receive the lock body. The sleeve has an annular groove on its interior face, which is positioned to mate with one or more detent balls in the cylindrical wall of the lock body. A plunger mechanism in the lock body can release the detent balls to permit insertion or removal of the body from the sleeve, and the plunger also releases the shackle when the combination is properly selected. The sleeve may be mounted in any sort of storage tube and enables the entire lock assembly to be stored in a secure and concealed manner.