🔍 Key Concepts

• Think about what a hermetic refrigeration system is and how technicians normally connect gauges to it. • Focus on the phrase Schrader core valve – this is the same basic mechanism used in many tire valves. • Only one of the illustrations shows a simple, straight access fitting that would be opened by the core depressor inside a hose coupling.

💭 Think About

• Which option looks most like a small service/access port that you’d leave on the system permanently for connecting gauge hoses? • Which device would NOT need to clamp around tubing or pierce it when installed, but instead relies on a small internal spring‑loaded core that is pushed open by the hose fitting? • Look closely at the shapes: which one resembles the kind of valve stem you’d see on an air line or tire, with threads for a hose to screw on?

✅ Before You Answer

• Verify which illustration has a single, central passage with internal core that would be unseated by a hose fitting, rather than by turning a large handwheel or piercing tubing. • Eliminate any valves that clearly act as shutoff or piercing valves (with a screw or clamp that drives a pin into the line). • Confirm that your choice would normally be called an access or service valve/fitting used to connect gauges to a sealed (hermetic) system.