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White triangular architect scale ruler 12 inches long with six die-engraved scales

Staedtler

Staedtler 9871931BK 12" Architect Triangular Scale drafting

SKU CH-3N9H-8QZGK MPN 9871931BK

White plastic triangular scale with six die-engraved scales for precise architectural drafting

  • Product typeProtractors - Stationery
  • Product colorWhite
  • Size details38 × 25 in
  • Sold asEach
  • Pack quantity1 each
  • Six scales on three sides cover multiple drawing ratios
  • Die-engraved graduations stay legible after heavy use
  • White plastic body gives high contrast for quick reading
  • 12 inch length fits standard drawing boards and briefcases
  • Lightweight at 0.14 lbs for comfortable all-day handling

Architect's triangular scale 12 inch

The Staedtler Mars 9871931BK is a 12 inch triangular architect's scale designed for precise drafting and measurement tasks. It suits architects, students and technical drafters who need a reliable manual scaling tool for plan work. The white plastic construction provides clear visibility of graduations under various lighting conditions. Sold as a single unit for individual use.

Six scales on three sides

Three flat faces carry six die-engraved graduations covering the common architectural ratios used in daily practice. The regular grooves give a positive feel when aligning the scale to a drawing edge. It handles routine plan checks and detailed layout work without the parallax issues of flat rules. Very large or non-standard ratios are not included on this tool.

White plastic with die-engraved markings

The moulded white plastic body resists warping and keeps the engraved lines legible after repeated use. No ink, batteries or software are supplied or required. The light weight of 0.14 lbs makes it easy to carry in a drawing tube or portfolio. No protective case or calibration certificate is bundled.

How it compares

Measured against everything we stock in Rulers & Technical Drawing Aids, at today’s prices. Recalculated every night.

Price $7.99
Cheaper than about 80% of the 41 comparable items (median $10.99).

Specifications

Product
Brand nameStaedtler
Product typeProtractors - Stationery
Product colorWhite
Size & build
Size details38 × 25 in
Shipping weight0.05 kg
Package size97 × 19 × 13 mm
In the box
Pack quantity1 each

Questions about this item

Will the 12" triangular scale sit flat on my existing 12" drawing board without rocking?

The scale is 12 inches long and weighs 0.14 lbs, so it lies flat on any standard drawing surface. Its triangular profile and regular grooves keep it stable while you align it with board edges or T-squares.

How do I verify the die-engraved graduations are accurate after unpacking?

Compare the six scales on the three sides against a known reference rule; the engraved lines should match at every increment without parallax shift.

Does the box include a protective sleeve or do I need to buy one separately?

The product is sold as a single white plastic triangular scale only; no sleeve, case or additional accessories are included.

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