Abracon FC4SD Resistance Weld SMD Crystals offer a 3.2MHz to 80MHz frequency range, tolerances down to ±10ppm, and stabilities down to ±5ppm. FC4SD crystals from Abracon feature a 300Ω maximum ESR rating, either a fundamental or 3rd OT operating mode, and 11.7mm x 5mm dimensions. The FC45D series has a -55°C to +125°C operating temperature range.