Roland WM-1 Low-Latency Wireless MIDI Interface, Bluetooth IOSProvides low latency MIDI communication between other WM series units and macOS iOS Bluetooth MIDI devices Fast mode delivers ultra low latency communication (3 ms) for timing critical applications Standard mode supports up to four total devices; Fast mode supports two total devices* Runs for about 60 hours on a single AAA battery Available WM 1D Wireless MIDI Dongle provides wireless MIDI for Windows computers and Fast mode support for macOS and iOS