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