"A midspan (PoE injector) can provide the necessary power level for PoE+ (Class 4) devices when the existing switch only supports standard PoE (Class 3). The midspan is placed between the switch and the device." - Axis PoE Solutions Overview "A midspan is recommended when extra power is needed but the switch does not support the higher class." - Axis Communications Academy, Network Video Fundamentals, 2022 References: Axis Power over Ethernet Guide Axis Communications Academy, Network Video Fundamentals, 2022 (p. 78)