Very wide 9.5mm ABS resin barrel with smooth flush knurled grip. Grip and taper are chrome-plated brass.
Very heavy at 22g and very tip-heavy, though I didn’t find either a problem.
The Pro-Use 171 employs the Safety Slide Mechanism, as used on the Press Man. This supports the lead much nearer the tip, protecting it from knocks and dropping, and allowing it to be used right down to the last millimetre.
You can switch lead-cushioning on or off by twisting the barrel, and you can adjust the lead sleeve length by rotating the tip. You can hide the sleeve entirely for safe carriage.
A major flaw is that the hardness indicator on the push button rotates freely and is completely useless. Minor flaws are that the supposedly removable clip is impractically tight and the sleeve adjustment in the tip needed lubrication. The design defects make this a bit pricey at £18 from Cult Pens despite its flexibility of use.