This piece is from the Japanese brand SMC and a:

Vacuum Regulator

Performance

This device is used to control vacuum pressure in pneumatic systems.

• Keeps the pressure within the set range.
• Adjusts from -100 to about -1.3 kPa.
• The amount of vacuum is controlled by the adjustment screw (knob).

Main specifications

• Model: IRV20-C06BG
• Brand: SMC Japan
• Type: Vacuum Regulator
• Pressure range: -100 to -1.3 kPa
• Working fluid: Air
• Connections: 6mm hose
• Adjustment accuracy: about 0.13 kPa
• Body: industrial and light

Applications

• Suction systems (Vacuum system)
• Pick & Place devices
• Packaging lines
• Industrial robotics
• Pressure control in air suction

Simple summary

• Vacuum pressure controller
• Specific for vacuum systems
• Precise adjustment with screws
• Reputable SMC brand of Japan

Approximate market price

• New: about 70 to 120 dollars
• Second hand: about 50 to 90 dollars

Depending on new or used and accessories like pressure gauge