A more modern sliderule made in 'Astrolon' plastic (polyvinylchloride). According to the numbers 471 on the back it was made in 1947 in batch 1 by Aristo (Dennert & Pape). A regular 10 inch 'system Rietz' sliderule.
Unlike later extruded models, this is milled from sheet material. Very straight and solid stock.
Glass window cursor with (circle area) C factor and kW to horsepower factors.
Have had this one since probably the mid eighties - have some memory of buying for 50 cents at a jumble sale. They'd only just been made properly obsolete then, so would have been ending up at the back of drawers. Or at jumble-sales :)
Pretty much a common, standard 'Rietz' sliderule that is surprisingly heavy and solid - feels 'precise'.