20 x 55 cm Slimline Background in grey / green basalt and sandy coloured gneiss finish. They are very realistic and are constructed from a firm, foam like material which has the benefit of being light and easy to cut to size if needed, but strong enough to resist the attentions of livefood which will often eat softer polystyrene. The clever design means that the backgrounds can be matched up next to each other to make a background for a large vivarium, joining together with a tongue and groove type edge that means the joins are virtually invisible. Even the colour and patterns match up.