A mixer (214, 314) configured to receive and dispense a fluid from a cartridge (212, 312) containing the fluid and including an outlet socket (116, 316) with a proximal wall (122, 330), the mixer (214, 314) comprising: a mixer conduit; an inlet socket (216, 318) sized to be engaged with the outlet socket (116, 316) of the cartridge (212, 312); a first (222, 340) and a second (224, 342) locking latch extending outwardly from said inlet socket (216, 318) and configured to snap into engagement with the proximal wall (122, 330) of the cartridge (212, 312); the second locking latch (224, 342) being positioned on an opposite side of said inlet socket (216, 318) from said first locking latch (222, 340); and a latch release mechanism (226, 322, 324, 326) coupled to said first locking latch (222, 340) and operable to disengage said first locking latch (222, 340) from the proximal wall (122, 330) without rotating the mixer (214, 314) with respect to the cartridge (212, 312); wherein said latch release mechanism (226, 322, 324, 326) includes a locking ring (226, 326) engaged with said first (222, 340) and second (224, 342) locking latches, said locking ring (226, 326) being moveable along said first (222, 340) and second (224, 342) locking latches from a locked position in which said locking ring (226, 326) compresses said first (222, 340) and second (224, 342) locking latches to prevent disengagement from the proximal wall (122, 330) to an unlocked position in which said first (222, 340) and second (224, 342) locking latches may be disengaged from said proximal wall (122, 330); the mixer being characterized in that said first (222, 340) and second (224, 342) locking latches include retention projections (242, 354) at the locked and unlocked positions and said locking ring (226, 326) includes corresponding detents (254,368) for engaging the retention projections (242, 354) to hold the locking ring (226, 326) at either the locked position or the unlocked position. a mixer conduit; an inlet socket (216, 318) sized to be engaged with the outlet socket (116, 316) of the cartridge (212, 312); a first (222, 340) and a second (224, 342) locking latch extending outwardly from said inlet socket (216, 318) and configured to snap into engagement with the proximal wall (122, 330) of the cartridge (212, 312); the second locking latch (224, 342) being positioned on an opposite side of said inlet socket (216, 318) from said first locking latch (222, 340); and a latch release mechanism (226, 322, 324, 326) coupled to said first locking latch (222, 340) and operable to disengage said first locking latch (222, 340) from the proximal wall (122, 330) without rotating the mixer (214, 314) with respect to the cartridge (212, 312); wherein said latch release mechanism (226, 322, 324, 326) includes a locking ring (226, 326) engaged with said first (222, 340) and second (224, 342) locking latches, said locking ring (226, 326) being moveable along said first (222, 340) and second (224, 342) locking latches from a locked position in which said locking ring (226, 326) compresses said first (222, 340) and second (224, 342) locking latches to prevent disengagement from the proximal wall (122, 330) to an unlocked position in which said first (222, 340) and second (224, 342) locking latches may be disengaged from said proximal wall (122, 330);