Edixa Rex series is similar to Edixa-Mat Reflex series, but with special Edixa bayonet mount. They are with interchangeable finder system.
This model was first called as Edixa Rex-C in catalogues. It has uncoupled externel CdS lightmeter. Its nameplate shows all caps or all lower case letters. 
See also the article Wirgin Edixa series (SLR models).