A glaucoma drain for non-penetrating deep sclerotorny is made of non-resorbable and hydrophilic synthetic material. The overall insole presents to a foot an effective upwardly facing support surface which has an effective surface tension which is lower than that of the underside of the foot. An injection conduit communicates the odorant tank with the pipeline. An oscillator is included that provides an oscillation signal that cycles between two states. The vehicle has a sound generator for substantially simultaneously emitting a first noise having increasing frequency and decreasing loudness, a second noise having increasing frequency and increasing loudness, and at least a third noise having increasing frequency by means of the sound transducer, in particular during increasing rotational speed of the electric drive.