1. Filter Type: The PZ series is designed for power lines, while the MMZ series is for signal lines. This reflects a fundamental difference in core material formulation and design optimization targets. Power line beads are typically optimized for suppressing low-frequency noise on power rails (e.g., DC-DC switching noise), offering more effective attenuation in lower frequency bands (e.g., 10-100MHz). In contrast, signal line beads focus on high-frequency noise (e.g., higher-order harmonics from digital signals) and signal integrity. Their impedance-frequency curves are generally "flatter" to minimize distortion of signal edges. Their attenuation characteristics differ across target frequency bands. Direct substitution may result in insufficient power noise suppression or excessive signal attenuation/distortion. 2. Impedance @ Frequency: PZ is rated 70Ω @ 100MHz, and MMZ is 80Ω @ 100MHz. Although the nominal impedance values are similar, the shape of the impedance-frequency (Z-f) curve varies between different bead series. At frequencies other than 100MHz—particularly in lower switching noise bands or higher RF interference bands—the actual impedance and filtering performance of the two parts can differ significantly, impacting EMI performance. 3. Manufacturer & Cost: TDK (MMZ) is a global leader in passive components. Its products generally offer more consistent performance, more comprehensive technical documentation, and higher market recognition, but at a higher price point. Sunlord (PZ) is a reputable domestic supplier offering good cost-performance. This difference may translate to varying risk levels concerning extreme temperature performance, long-term reliability, or batch-to-batch consistency. While potentially acceptable for consumer applications, careful evaluation is advised for industrial, automotive, or other high-reliability applications.