Carabiner designed to be printed on the Markforged Mark One with either Kevlar or Fiberglass reinforcement. Flexible where it counts but incredibly strong and very stiff where it needs to be. Clean up the latch surfaces with a craft knife for a better latch closure. This can be printed on a standard desktop printer in ABS/PLA and may still work, but it will not have the strength of fiberglass/Kevlar and the flexibility of nylon.Print with either Kevlar or Fiberglass, concentric fiber: 2 rings, 8-12 layers. If dyeing, use additional layer of fiber. Don't use carbon fiber. it doesn't fit correctly in the latch and is too stiff.