Described are multi-chambered vessels comprising a first chamber, a second chamber, and a seal comprising a first member and a second member, wherein the first and second members are engageable with one another to form a barrier separating the first and second chambers. The first and second members are disengageable from one another to open a channel between the first chamber and second chambers. The vessels allow communication between the first and second chambers at a desired time, for example in order to contact components contained within the chambers or in order to sequentially release components or doses of components from the vessel. Also provided is a kit comprising a seal of the invention. The kit allows a single-chambered vessel to be converted into a multi-chambered vessel capable of controlling communication between the chambers at the final stage of the filling process.
