Back in January 2012 I penned the in depth review below of a Power Jet
“Here sits a Power Jet. It will be going in a Dellorto 30mm Carburettor that will go on the TS1225. Having this little toy bolted to the carb means you can instantly adjust the carb for the conditions your riding in with a wee twiddle of the dial.”
You can purchase these from Cambridge Lambretta Workshops here.