My pressure cooker shows Keystone Mfg. Co., as the "brand name". During my internet research, (for the manual), the brand-name, "Deni", is associated with the Keystone Mfg. Co.'s products. My cooker doesn't show the name "Deni" on it anywhere. All of the pic's of the cookers are different looking than mine. It was given to me without the manual and I would sure love to have it. Can u help