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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 the finished surface.  The tape’s outer edge features a diamond-punched pattern for a superior bond and 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 the laminated surface.
  • Pre-treated to accept primer or paint
  • Paper will not fuzz-up during sanding like paper and mesh tapes



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

Code Approvals & Performance 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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