Grey Proto-Pasta Steel? Filled PLA Grey Beard . Posted on April 22, 2020 I have to track this material again. I believe it is the steel. I will update the post. Steel-filled Metal Composite PLA Share this:ShareFacebookTwitterPinterestRedditLike this:Like Loading... Post navigation Protoparadigm/MadMaker Citrine PLA3D-Fuel Natural Workday PETG Leave a Reply Cancel replyYour email address will not be published. Required fields are marked *Comment * Name * Email * Website Notify me of follow-up comments by email. Notify me of new posts by email. Δ This site uses Akismet to reduce spam. Learn how your comment data is processed.