- Extension splint (also called "Wynn Parry" or Capener splint) uses coil springs placed lateral to and in line with PIP joint
- Curved proximal and distal supports distribute pressure evenly
- Extension assistance adjustable by altering distal strap
- Provides uniform force throughout the range and offers stronger spring tension at an extended position than models #501 or #602
- Force: Full extension = 2.75 lbs.