A cable lock and seal device with features preventing the locking mechanism from engaging the cable fibers too tightly to cut or fray is disclosed. A conventional device is made up of a body (10) and a cover (20) halves to complementarily form a block enclosing therewithin a passage (30) and a chamber (50). The body (10) is integrally formed with an anchor block (12) in which one end of a cable (14) is anchored. The other free end of the cable (14) may be inserted into the passage (30) which is preferably curved upward in traversing the assembled body-and-cover block. The chamber (50) is adapted with a ramp (52) rising towards the passage (30), a slot (54) for retaining a spring (56) which second end is disposed to urge a locking wheel (53) up the ramp (52) against the passage (30). The improvement lies in providing a rib (51) along the lower wall of the passage (30) proximal to the top end of the ramp (32) so that the urging of the locking wheel (53) by the biasing means (56 or 58) up the ramp (52) is restrained when the locking wheel's axle (55) engages the rib (51) and limits the wheel (53)'s further entry into the passage (30) upon having sufficiently engaging the cable (14). While preventing the wheel edge from over-engaging and cutting the cable fibers it also prevents the withdrawal of the inserted cable.