This is a CPU 948 PN/DP Module from Siemens. It is designed for use with SIMATIC S7 PLCs and is part of the SIMATIC S7-900 series. This particular model is a CPU 948 Part Number/Diagnostic (PN/DP) module which features onboard RAM 32 KB and two different communication interfaces: PROFINET and PROFIBUS. The CPU 948 PN/DP module provides up to 64 discrete and 16 analog inputs, as well as 32 discrete and 16 analog outputs. It also provides numerous system functions such as program execution, master clock, data recording, and user-defined functions. The 6ES7953-8LL31-0AA0 CPU 948 PN/DP module is ideal for applications that require precise control, high speed data transfer, and are cost conscious.