GwliUni 4Pcs MPO Single Mode Female Loopback Plug 12 Fiber Core 6 Channels TypeThis 4-piece MPO single-mode female loopback plug is designed for testing 40G and 100G fiber optic networks. It supports 12 fiber cores across 6 channels in Type A configuration for QSFP testing and network system diagnostics. The loopback tester detects signal return abnormalities by transmitting signals back to the receiving end. Features low insertion loss and high return loss for accurate testing across temperatures from -40 to 75°C.MPNMPO LoopbackEAN9331908376920Itemweight0.07 poundsProductdimensions5.3 x 0.7 x 5.7 inchesStyleMPO Female-12 Core 6 Chann