Frame Structure: Mainstream options include North American maple, oak, or beech (quiet, stable, and typically fixed-frame); aerospace-grade aluminum alloy (lightweight, rust-resistant, and foldable); and cold-rolled steel (high-strength, impact-resistant, and suitable for commercial use).
Carriage Surface: Features an interior of 45D–50D high-density foam, wrapped in imported fiber leather or a non-slip PU layer to ensure proper support, resilience, and traction.
Resistance System: Core springs typically utilize high-carbon manganese steel or Grade 5A piano wire, subjected to quenching treatment to guarantee tensile strength and a fatigue life of over one million cycles.
Connection Hardware: Pulleys, hooks, and rail components generally use 304 stainless steel or high-strength nylon/alloys, balancing smooth operation with corrosion resistance.
