Z1OwnersClub GB

Can anyone identify a set of unusual looking carburettors ?
Previous owner said Z900.
Code on inlet flange is Z12 00
Carb is 26mm bore VM26
Only single idle mixture screw on top side - no volume control screw underneath.
Unusual looking synchronisation mechanism under top covers (3 screw cover) NOT the usual single screw/locknut adjuster. Has a 2 part mechanism with a spring, a bolt and a screw / locknut - looks just like the mechanism in VM29 SS Smoothbore. Not a smoothbore carb though.
Outside of inlet horn where Airbox fits has only one ridge / ring around the outside - the normally bigger second ridge (closest to carb body - stops the airbox pushing on too far) is missing except for a short section approx 8mm at the top / 12.00 position.
Float bowls, floats etc look like usual Z900.
Choke plunger lifters look like Suzuki style (but could have been changed - carbs have clearly been worked on / dismantled)
ALL SUGGESTIONS WELCOME !!

Picture?

Single mixture screw means they are Kawasaki.
Only Suzuki VM's had both.
Smooth bore style lifters were on some early vm26mm's.
Think they may have been one year only.

Early Z900 ........

As far as I can see they are 1976 Z900 & 1/2 year early 1977.
1978 had the standard KZ1000 26mm, they had the air screws under neath the bodies. And Factory had a small white plastic limiter cap on it to limit playing with them.

Thanks for the responses gents. Just I'd never seen another set the same in over 40 years ! Every day's a school day .....

Thanks for the responses gents ! Just I'd never seen another set the same in over 40 years. Every day's a school day....