There was still plenty of experimentation with aluminum frames in the mid-1980s. For road bikes, constructions with glued aluminum frame tubes were the way to go. Many manufacturers have not yet ventured into welded frames, let alone mountain bikes. 

Germany’s Kettler, known for aluminum garden furniture, thought the time was right to use its experience for the production of this Alurad ATB. Lightweight construction wasn't a goal yet, given the bike's 16kg weight.

Despite intensive advertising, including the claim of the first ascent of Mont Blanc by ATB, it still took several more years for welded aluminum mountain bikes to become a common thing.