These microscope slides are machine-made with a thickness and size useful in petrographic studies. Choice of three styles: 
MA 158,  46mm x 27mm,  annealed glass slide,  1.16mm to 1.27mm thickness, packaged 144 slides per box;
MA 160,  48mm x 28mm,  crystal slide,  1.35mm thickness, packaged 100 slides per box;
MA 161,  46mm x 26mm,  glass slide,  1mm thickness; packaged 50 slides per box.

Slides are made in Germany.   Shipping weight 2 lbs.