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You can still get this classic freeware plugin dating back to 1999 over at Wayback Machine. The main difference between the 'Pro' version and this one, is that the Pro has 12 note polyphony and supports pitch bend and mod wheel. The free version has 8 note polyphony and does not support those MIDI features.

Not a bad synth, but super limited. No pitch bend or LFO means something like vibrato wouldn't be possible, nor pitch slides. But it's oscillators and filter are way better than on Neon for example. And all parameters are open to automation. Good for old school sounds.

Seems to have an issue though: the pulse width affects the DC offset of the signal, which could be a problem in some cases.

The WASP soft synth which came out 2000 for Orion Pro (then later licensed for Fruity Loops 3.0) had a much better pulse oscillator in comparison.