Abstract: A hair measuring assembly capable of being operated by a single hand of a user and including a collection assembly, including a hair retaining and measuring portion movably mounted on a body and selectively disposable between a collecting position and a retaining and measuring position. The single handed manipulation of a hand grip, concurrently disposes a plurality of two grip segments into either an open or a closed orientation, thereby forcing the hair retaining and measuring portion between the collecting and hair retaining and measuring positions. A “single use” cartridge for carrying out the collection, retention and measurement of hair and also hair breakage is presented. The “single use” cartridge includes suitable structure for mounting and operable attachment to the hair measuring assembly by a person, without regard to whether he or she is left-handed or right-handed.