PolyFlex (1.75 mm; 750g) Black Flexible : PolyFlex features a Shore A hardness of 90-95A and a large strain-to-failure of over 401% Printer Compatibility: Flexible filaments are known to be difficult to work with Well not any more PolyFlex is designed to be compatible with almost all desktop FDM/FFF printers and requires no hardware modification Flex-up Your Imagination : The soft and flexible nature of PolyFlex opens up a new dimension of what one can do with desktop 4D printers, clothing, shoes, wearables, prostheticsyou name it