in  jeremiah joined his brother charles in starting their own lock company chubb chubb made various improvements to his lock his  improved design didnt require a special regulator key to reset the lock by  his keys used six levers rather than four and he later introduced a disc that allowed the key to pass but narrowed the field of view hiding the levers from anybody attempting to pick the lock the chubb brothers also received a patent for the first burglar-resisting safe and began production in 