"Optec Fast Focus secondary focuser"
Near as I can tell this is no longer sold or supported, which is really too bad.
Does anyone have different info? (i.e. a retailer?)
BTW, curving the wires will avoid an obvious diffraction "spike" but actually throws more light into a diffuse diffraction haze.? But probably most people prefer that nearly undetectable haze to an obvious?single spike. Although there are surprising number of refractor users who paste artificial spikes onto their images to make X-mass stars, so you could add another wire to make a complete cross... <g>
Stan
