SR144TiZN High Speed Dental Handpiece Bearing – Hybrid Ceramic, ABEC-7/P4 Precision. Stainless steel rings (440C) with Silicon Nitride (Si3N4) ceramic balls. Torlon/Phenolic cage for heat resistance, speeds up to 450,000 RPM. Precision replacement for KaVo, NSK, W&H, Sirona, Midwest, Bien-Air and major dental handpiece brands. Delivers smoother operation, longer turbine life, and quieter performance. Key Specifications: Modell: SR144TiZN Type: Miniature deep groove ball bearing (hybrid ceramic) Innendurchmesser (ID / D): 3.175 mm (1/8 inch) Außendurchmesser (OD / D): 6.35 mm (1/4 inch) Breite (B): 2.38 mm (3/32 inch) or 2.78 mm (7/64 inch) [variant-dependent] Ringmaterial: AISI 440C stainless steel Ball Material: Silicon Nitride (Si3N4) ceramic Precision Grade: ABEC-7 / ISO P4 Maximum Rotational Speed: 350,000 – 500,000 RPM Weight: Approx. 0.2–0.4 grams RPM: 400,000 Ceramic balls are standard in our high-end series for their lightweight properties, which reduce centrifugal force, lower heat generation, and enable higher maximum speeds.