I recently purchased these grips, because of their symbolic price and 'cause I need always thumbrest grips. They are for a N frame.
I thought to be an "expert" , however I can't identify the brand . In this case, i well understand Socrates , the ancient greek philosopher, when he said γηράσκω δ' αἰεὶ πολλὰ διδασκόμενος " gerąsko d'aiči pollą didaskņmenos " (I grow old always learning many things).