Abstract: Radial block copolymers are mechanically combined with additional polymeric materials to form plastic compositions having a high degree of clarity so that they can be substituted for polyvinylchloride plastic compositions in the fabrication of such devices as intravenous and blood tubing, containers for intravenous solutions and blood fractions, functional parts of intravenous administration equipment such as sight and drip chambers, needle adapters and miscellaneous assemblies for contact with intravenous fluids. The compounds of this invention can also be utilized for catherization, bodily drainage systems, and as pharmaceutical closures, resealable injection sites and syringe plunger tips.