These 1.75mm PLA filaments are specifically designed for FDM printers such as the Flashforge, Leapfrog Creatr and Xeed, FELIXprinters Felix, Code p-West Builder 3d Printer, PP3DP Up Plus 2, The Up Box and the Up Mini, Makerbot Mk7 or later, RepRapPro Prusa and Huxley, Solidoodle and LulzBot.
These are high quality printer filaments with good dimensional accuracy 1.75 +/_0.10mm.
PLA (polylactic acid) is a an natural bio-degradable polymer derived from either corn, maize or potato starch. It has no odor a low melting point (175 - 200 degrees C) which makes it less susceptible to warping during the printing process.
PLA can be used to produce case metal parts. The PLA can be used as a direct replacement for Wax in the lost wax process, as it will evaporate away during burn out. You can see a step by step example of Lost PLA casting here-