The ZULU was a shotgun using surplus French 'Tabatiere' breech actions from the Franco-Prussian War and the one for sale is one of those. The Tabatiere was a stop gap conversion using a form of the Snider system.

Guys,
 
Been incommunicato for a couple of weeks... Thanks for putting up the PATENT PDF... This is marvelous and quite informative.
 
The work I've been doing on the Cornish, using Lucs photos gives a pretty close approximation to the original patent specs, though I have beefed up certain areas of obvious weakness and decreaced the firing pin angle considerably... As things progress I will post the doings here.