$25–45 USD. If you see a $5 dongle, it’s almost certainly a CIR (Consumer IR) remote receiver, not an IrDA data adapter.
The U2IRDA Mini 4 Mbps FIR USB IrDA adapter has several applications in various fields. For example, it can be used in business settings to transfer files between devices quickly and efficiently. It can also be used in healthcare settings to transfer patient data between devices. u2irda mini 4 mbps fir usb irda 20 portable