The receiver supports 4K polling rate (for A5 Pro / A5 Pro Max models) or 8K polling rate (for series like A7 / M7) when paired with a compatible MCHOSE mouse.
It is a USBdongle type (nano receiver) that you plug into your PCs USB port.
It is listed as MCHOSE A5/M7/A7/G7 Max 4K/8K Receiver for Wireless Mouse on the official MCHOSE store.
Compatible with wireless models in the A5 series (such as A5 Pro / Pro Max) which specify 4K receiver support.