A reconstitution device comprising: a device suitable for mixing a first component with a second component, said device comprising: first and second housings (12, 14); said first and second housings (12, 14) being engageable together; a conduit having an internal passageway formed in said first housing, said internal passageway having a dispensing end and an inlet end; a first plunger mounted in said internal passageway proximate said dispensing end; a second plunger mounted in said internal passageway proximate said inlet end; a third plunger mounted in said internal passageway intermediate said first and second plungers (50, 52), said first and third plungers (50, 54) defining a first compartment therebetween, said second and third plungers (52, 54) defining a second compartment therebetween; a plunger rod at least partially within said internal passageway at said inlet end; a moveable member located in said second housing; said moveable member engaging said first plunger; said moveable member having at least one leg (43, 49) extending upwardly therefrom, said upwardly extending leg (43, 49) engaging said first housing such that said first and second housing cannot be disengaged from an initial first position, the arrangement being such that when said plunger rod is moved to commence transfer from said second compartment to said first compartment, said leg (43,49) on said moveable member disengages from said first housing to permit rotatable movement of said first and second housings (12, 14) and a shearing channel formed in a side wall of said conduit to permit mixing of contents located in said first and second compartments (74, 76). a device suitable for mixing a first component with a second component, said device comprising: first and second housings (12, 14); said first and second housings (12, 14) being engageable together; a conduit having an internal passageway formed in said first housing, said internal passageway having a dispensing end and an inlet end; a first plunger mounted in said internal passageway proximate said dispensing end; a second plunger mounted in said internal passageway proximate said inlet end; a third plunger mounted in said internal passageway intermediate said first and second plungers (50, 52), said first and third plungers (50, 54) defining a first compartment therebetween, said second and third plungers (52, 54) defining a second compartment therebetween; a plunger rod at least partially within said internal passageway at said inlet end; a moveable member located in said second housing; said moveable member engaging said first plunger; said moveable member having at least one leg (43, 49) extending upwardly therefrom, said upwardly extending leg (43, 49) engaging said first housing such that said first and second housing cannot be disengaged from an initial first position, the arrangement being such that when said plunger rod is moved to commence transfer from said second compartment to said first compartment, said leg (43,49) on said moveable member disengages from said first housing to permit rotatable movement of said first and second housings (12, 14) and a shearing channel formed in a side wall of said conduit to permit mixing of contents located in said first and second compartments (74, 76). first and second housings (12, 14); said first and second housings (12, 14) being engageable together; a conduit having an internal passageway formed in said first housing, said internal passageway having a dispensing end and an inlet end; a first plunger mounted in said internal passageway proximate said dispensing end; a second plunger mounted in said internal passageway proximate said inlet end; a third plunger mounted in said internal passageway intermediate said first and second plungers (50, 52), said first and third plungers (50, 54) defining a first compartment therebetween, said second and third plungers (52, 54) defining a second compartment therebetween; a plunger rod at least partially within said internal passageway at said inlet end; a moveable member located in said second housing; said moveable member engaging said first plunger; said moveable member having at least one leg (43, 49) extending upwardly therefrom, said upwardly extending leg (43, 49) engaging said first housing such that said first and second housing cannot be disengaged from an initial first position, the arrangement being such that when said plunger rod is moved to commence transfer from said second compartment to said first compartment, said leg (43,49) on said moveable member disengages from said first housing to permit rotatable movement of said first and second housings (12, 14) and a shearing channel formed in a side wall of said conduit to permit mixing of contents located in said first and second compartments (74, 76).