Note: This flash is not compatible with ZV-1F, A9III, A99, A77, A350. This flash is not compatible with Rebel SL3, 250D, T7, 1500D, 2000D, T100, 3000D, 4000D, 200DII. This flash is not compatible with X-A3, X100F, X100T. Troubleshooting for failure to flash: When using the flash for the first time, wait for the flash recycle indicator to turn green, indicating recycle is complete. If the indicator remains red or white, replace the battery with a new or fully charged one. If the flash does not work, access the camera's menu and set the flash mode to "Manual / M". Troubleshooting for not working as expected: Shutter Speed setting: This flash does not have TTL function or high-speed sync. It is recommended to use a shutter speed below 1/200s; otherwise, photos may exhibit black or white edges. Sensitivity setting: It is recommended to set ISO sensitivity to 100, then adjust higher based on lighting conditions. Aperture setting: It is recommended to set the aperture to f/2.8, then adjust based on lighting conditions. Long-lasting Lithium Battery: Built-in 3.8V/470mAh lithium battery provides stable performance and delivers up to 440 full-power flashes with approximately 3 seconds recycle time. The iM20 features a USB-C charging port for fast recharging. Compact Design: The iM20 measures 1.54 x 1.5 x 1.16 inches and weighs only 31g, making it small and lightweight enough to fit in a pocket or handbag for easy portability during street photography or travel. Compatible Mountings: Compatible with ZVE10, ZV1, A7III, GR3, GR3X, F1. Not compatible with ZV-1F. Camera Flash Type: Hot shoe Flash Sync Speed: 1/250s Product appearance and printed text may vary by batch, but this does not affect functionality. Color: Material: ABS Package Contents: 1 x iM20 Camera Flash Only the items listed above are included; other products are not included. Note: Lighting and display differences may cause slight variations between the color of the item in images and the actual product. Measurement allows an error of +/- 1-3cm.