It can hold cartridges, and hair (4)
I believe the answer is:
clip
'it can hold cartridges and hair' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for clip that I've seen before include "Fastener - part of film" , "Piece of film etc" , "Cut, trim" , "sort of joint" , "Cut short; cartridge holder" .)