the purity of grey top puretropin gh is higher than orange top puretropin gh ,
orange top puretropin gh :10iu/vial-----100iu/kit
grey top puretropin gh :15iu/vial--150iu/kit
someone love orange top , someone love grey top , it is decided by yourselves.
the quality of them are top , we are sure, maybe you can have a try , thanks , :0