The Zoomatic strainer came in two styles; up to around 1967, the slider was narrow with two holes to use string. Beginning sometime in 1968, the slider was lengthened and used a clamp bar to use "normal" length wires with filament tape strips. All the drums that used the Zoomatic strainer also used the Leedy extended butt.
For the Zoomatic that had the narrow slider and two holes, Slingerland used the odd half-extended wires that went off the end opposite the Zoomatic. For the newer Zoomatic that used the clamping bar, Slingerland used the same length of wires as all their other 14" snare drums.
While those half-extended wires may be factory correct for the earlier Zoomatic, they can be a pain to set up properly. That, plus finding these wires can be next to impossible! Puresound offered them for a bit, but they were discontinued some years ago! Just use "normal" length wires for all Zoomatic strainers!
Attached are some pictures of a 1966 Artist I recently sold. It uses the half-extended wires.
-Mark