It looks like you’re referring to a pressure  transmitter used on MWM / Caterpillar gas engines, with an OEM from WIKA.

Here’s how your details break down:

• Part description: Transmitter

• OEM: WIKA

• Current part number: MWM 12323777

• Old/previous number: 12404223

• Application:

  • MWM TCG 2016

  • MWM TCG 2020

  • MWM TCG 2032

  • CAT CG170

What this likely means

• 12323777 is the updated/replacement part number for 12404223

• The transmitter is likely used for oil pressure, gas pressure measurement, depending on the exact engine configuration

• Since it’s OEM WIKA, it’s typically a high-accuracy industrial sensor matched to MWM/CAT control systems

What you should confirm before ordering

To avoid getting the wrong unit (these vary a lot), double-check:

• Measurement type (pressure )

• Range (e.g., 0–10 bar)

• Output signal (commonly 4–20 mA)

• Electrical connector type

• Thread/connection size (e.g., M14)

Cross-check tip

If you're sourcing:

• Use both numbers (12323777 and 12404223) when contacting suppliers

• Mention engine model + serial number for exact matching