### Star Shaped Inner Wall This filament guide tube features a unique star shaped or flower pattern inner wall structure. The concave convex design significantly reduces the contact area between filament and tube wall, minimizing friction resistance for smoother feeding. ### Low Friction Performance The star shaped inner wall design lowers feeding resistance by at least 30 percent compared to smooth bore tubes. This ensures reliable filament delivery even at high speed printing up to 500mm per second. ### TPU Friendly Design Flexible filaments like TPU below 95A hardness are prone to buckling and jamming in standard tubes. The star shaped inner wall eliminates this problem, allowing soft materials to feed smoothly every time. ### Precision Fit for U1 This replacement tube matches the U1 original specifications with 6mm outer diameter and 650mm length. It connects securely with quick release fittings on both ends and works with all four independent toolheads. ### Translucent Gray Visual Monitoring The semi transparent gray color allows you to easily see filament movement through the tube. This helps quickly identify feeding issues or filament jams before they affect print quality.