... except polyethylene. Polypropylene, teflon, and very porous surfaces, which require special treatment.To open tube:1. Unscrew entire nozzle & cap unit ... top of tube. Point tube away from face, Press to puncture.Do not squeeze tube while puncturing. After puncture is made, replace ... eye with quantities of plain water, do not try to remove by rubbing or applying solvents, in case of pain or discomfort, ...