Multi-instrument configuration
Connect instruments in a multi-instrument configuration to create an up to 4 channel, highest bandwidth, and highest sample rate
system with synchronized trigger and sample clock. 
About Tektronix oscilloscopes  
46  DPO70000SX, MSO/DPO70000DX, MSO/DPO70000C, DPO7000C, and MSO/DPO5000B Series