Disclosed is a cover for an injector having a needle, a needle cap, and a needle cap remover, the cap remover being a coupler for a needle cap and a user handle, the user handle having a protruding element opposite the coupler, the protruding element having a short dimension and a long dimension, the cover comprising: at least one adhesive layer covering a surface of an outside of the injector; at least one liner layer, covering the adhesive layer, an extension extending beyond the surface; a first aperture through the adhesive layer and the liner layer aligned to an opening in the surface, the first aperture sized and shaped for passage of the coupler therethrough; and a second elongated aperture, through the extension, having a length being shorter than the short dimension and shorter than the long dimension of the protruding element.