THE CLASS OF CH STARS ARE POPULATION II STARS WHICH ARE ALMOST ENTIRELY BINARIES WITH EVOLVED PRIMARIES AND WHITE DWARF SECONDARIES FORMED WHEN THE WHITE DWARF S PROGENITOR UNDERWENT A PHASE OF MASS TRANSFER TO ITS COMPANION AFTER THE STAR HAD ALREADY DREDGED-UP CARBON-RICH MATERIAL. THE MASSES OF THE WHITE DWARFS IN THESE SYSTEMS ARE QUITE DIFFICULT TO MEASURE DIRECTLY BECAUSE THE SYSTEMS ARE NOT IN ROCHE-LOBE OVERFLOW. THEY SHOULD HOWEVER BE WIND-FED SYMBIOTIC STARS POTENTIALLY ALLOWING THE MASSES TO BE ESTIMATED FROM THEIR X-RAY SPECTRA. SURPRISINGLY NONE HAS BEEN DETECTED IN X-RAYS YET AND NO GOOD OBSERVATIONS SEEM TO EXIST. THE BRIGHTEST OF THESE OBJECTS SHOULD BE SLIGHTLY BELOW ROSAT LIMITS BUT EASILY DETECTABLE BY XMM-NEWTON. HERE A PILOT STUDY OF THE FOUR BEST CANDIDATES IS PROPOSED TO DETERMINE IF THEIR X-RAY FLUXES ARE AS HIGH AS EXPECTED. REGARDLESS OF HOW THE RESULTS TURN OUT WE WILL DEVELOP KEY UNDERSTANDING OF MASS TRANSFER AT LOW METALLICITY AND IF THE SOURCES ARE AS BRIGHT AS EXPECTED WE CAN THEN PLAN MASS ESTIMATION WORK.