{HEAD ~ Fluid} from the environment is imbibed through a semipermeable plug into the water swellable agent chamber and the active agent formulation is released through {TAIL ~ a back diffusion} regulating outlet 
{ HEAD ~ Fluid } from the environment is imbibed through a semipermeable plug into the water swellable agent chamber and the active agent formulation is released through { TAIL ~ a back diffusion } regulating outlet
HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH