The first plastic models were injection molded in cellulose acetate (e.g. Frog Penguin and Varney Trains), but currently most plastic models are injection-molded in polystyrene, and the parts are bonded together, usually with a plastic solvent-based adhesive, although experienced modelers may also use epoxy, cyanoacrylate, and white glue where their particular properties would be advantageous. While often omitted by novice modellers, specially formulated paint is sold for application to plastic models. Complex markings such as aircraft insignia or automobile body decorative details and model identification badges are typically provided with kits as screen-printed water-slide decals.