The WG3014 is a 13-channel multimode variable optical attenuator engineered for parallel attenuation and power balancing in multimode optical module production and device testing. Its 13 independent attenuation units operate at 850±20nm across a 35dB range, adjustable in 0.1dB steps—a channel count that sits deliberately between compact 8-channel units and high-density rack systems, matching production fixtures that need more than eight but fewer than sixteen simultaneous multimode paths. Open-loop mode sets a fixed attenuation value for fast line tuning, while closed-loop mode locks onto a target output power and automatically compensates for input drift. Per-channel output power monitoring (−50 to +10dBm, ±0.2dB accuracy) provides real-time verification without external meters, and <2.0dB insertion loss with low mode-dependent loss preserves multimode signal integrity. USB and LAN interfaces support full program control for ATE integration, while FC/PC (50/125 or 62.5/125 fiber) connectors and a standard 450×400×88mm chassis suit production floors and lab racks. The WG3014 is purpose-built for SR4/100G/400G multimode module receiver sensitivity and eye-diagram batch testing, ROSA/BOSA multimode characterization, and multimode fiber harness production inspection—wherever thirteen multimode paths must be attenuated and verified in lockstep.