🔍 Key Concepts

• Look closely at the note near the threaded portion of the drawing, not just the shape of the threads. • Recall the standard thread designations such as NC (National Coarse), NF (National Fine), Acme, and Square, and how they are usually written on mechanical drawings. • Consider the difference between a thread form name (like acme or square) and a series designation (like NC).

💭 Think About

• What specific letters and numbers are printed right next to the threaded area, and what do they usually mean on a machine drawing? • Does the drawing actually show the detailed flank shape of the thread (square vs trapezoidal vs V‑shape), or is it using a simplified symbol with a written designation instead? • Among the answer choices, which one directly matches the written thread designation you see on the drawing?

✅ Before You Answer

• Verify the exact text that follows the thread callout (it should look like diameter – threads per inch – series – hand). • Confirm whether ACME or square is explicitly written anywhere on the drawing (is it, or is only a standard series like NC given?). • Make sure you understand that NC stands for a specific thread series and decide which answer choice corresponds to that series.