Slotted capstan screws
Slotted capstan screws may be used both as fastening and adjusting screws. They are primarily designed for use in electrical engineering and may be tightened by means of a sliding tee bar where it is not possible to use a screwdriver. Locking wires are often attached to the cross holes for securing purposes.

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STRUCTURAL FLUSH BREAK PULL MANDREL SELF-PLUGGING BLIND RIVETS
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