Strait-Flex® Perfect-90°

Finishes inside 90° and off-angle corners

Perfect-90º ensures a clean, sharp corner without the risk of damage from a taping knife.

Application(s): Drywall

Perfect-90º is twice as fast and twice as strong compared to conventional paper or mesh tapes. No compound is needed over finished surface.  The tape’s outer edge features a diamond punch pattern for a superior bond, faster drying, with no rippling or blistering.

  • Memory-free hinge produces straight inside corners and perfect angles
  • Reinforced paper backing provides strength and rigidity
  • Spans small gaps in drywall, no back filling needed
  • Finishing compound is not required over laminated surface. Pre-treated to accept primier or paint
  • Paper will not fuzz-up during sanding like paper and mesh tapes




  • Fold Perfect-90º in half at center crease with print size facing each other. For intersecting corners, cut ends at 45º angles. For inside corners, fold less than desired angle with print side facing out.
  • With a 5” or 6” taping knife, apply a smooth, liberal coat of compound to corner.
  • Press Perfect-90º into the wet compound. Adjust if necessary to create a straight line.
  • Wipe down tight with taping knife using a little additional pressure on the outer edges of Perfect-90º. Let dry completely several hours or overnight.
  • Apply final coat to perforated edge only. No compound is needed over finished area of tape. It’s ready to paint. Let dry completely over several hours or overnight.
  • Sand lightly with 120 grit sandpaper. Perfect-90º will not fuzz-up like paper or mesh tapes

ASTM & Code Standards:



All stored materials shall be kept dry. Materials shall be stacked off the ground, supported on a level platform, and protected from weather and moisture.


Product Submittal Sheets

Click the below Product Code to view Submittal/Tech Datasheet.

Product Code Description
P90-100 Strait-Flex® Perfect 90°

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