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Crystal 40.0000MHz 20PF SMD - ECX-53B - ±50ppm - ±30ppm - 20pF - 30 Ohm - Fundamental - -20°C ~ 70°C - 4-SMD - No Lead (DFN - LCC) - 0.197" L x 0.126" W (5.00mm x 3.20mm) - 0.033" (0.85mm)