The Siemens 6ES7413-2XG00-0AB0 is a SIMATIC S7-400 CPU 413-2 DP central processing unit. It carries a multi-point interface (MPI) and an integrated PROFIBUS DP interface, with 72 KB of working memory. This is a rack-mount CPU for the S7-400 chassis — it's not a standalone brick like the S7-1200 or S7-1500. You slot it into a UR1 or UR2 rack alongside power supply, I/O, and comm modules.
What the 72 KB working memory means for your application
72 KB of working memory is modest by today's standards — enough for a medium-sized logic program with a few hundred I/O points and some data blocks. If your project is pushing into the thousands of instructions or heavy data logging, you'll want to step up to a 414 or 416 CPU. For a dedicated machine cell or a process skid with moderate logic, this CPU is sized right.