Proto-pasta Composite Conductive PLA, 1.75 mm 500 g High electrical conductivity of 15ohm-cm suitable for lighting LEDs, touch sensors and other electronics. Comes on fully corrugated recyclable spool with standard dimension Dark Black in color with good printing on PLA machines Processing is comparable to standard PLA. No heated bed required, but it may improve results. Process may be less consistent on smaller nozzles (&lt;4mm) and/or bowden-type machines We recommend printing this material at 220c-230c using a 4 mm or larger nozzle. Please note that this filament is more brittle than normal PLA and requires more careful handling to prevent breakage Designed and manufactured in the USA with quality and customer service as top priorities. USA-sourced packaging and labor