I had to pick up a set of Bison Merkava IV decals for another project so figure I might as well build a Merk. Planning on a Iv LIC. While researching I found two add ons. One is listed as the Trophy system, the other is listed as Windbreaker and looks like an escapee from the Star Wars prop department. When researching these it says Trophy/ Windbreaker are the same program, which is fitted to both sides of the turret. The other system , what little I found impies it was only used on Merk III and Nagmachon. Anybody able to be mystify this?

The one listed as Windbreaker is called a Droid- Ithink it was mislabeled by the model companies. The IV definitely uses the droid. Check out this thread https://armorama.kitmaker.net/forums/169520

The "Mei'l Ruach" (Windbreaker) system sold abroad as "Trophy". In other words, the "Windbreaker" is simply a translation of the Hebrew name of the system.

Little known about the so called "Droid", as it remains classified. Anyhow, the "Trophy/Windbreaker" and the "Droid" are two different systems.
Hope that helped.
Israel

Are the Droid and Windbreaker systems also in use independently together on Merkavas IV?

I don't think so, but don't take my words for granted...

With little intel and taking a SWAG from it's look, I'd guess Droid is a jammer of sort (like the system on the T-90 )or warning sensor.