GNC sold Pro Performance Ultimate Power Grips, a series of metal-handled torsion-spring grippers. A September 2011 product notice in Iron Man magazine documents their sale through GNC stores and GNC.com.[1]
Models and sets
The advertised range comprised six strengths, packaged in two groups:[1]
| Set | Advertised strengths |
|---|---|
| Beginner | 50, 100 and 150 lb |
| Advanced | 200, 250 and 300 lb |
These numbers identify the marketed models. They should not be read as RGC measurements.
Handle variations
Contemporary owners reported more than one handle design. In February 2012, a purchaser described a newer set without the smooth middle band or notch seen on earlier examples. This helps explain differences between surviving GNC grippers without assuming that every example had identical handles.[2]
Measured examples
Owner measurements show the difference between the label and measured closing resistance. Jason Steeves' May 2012 collection table includes GNC 200 specimens at 116.8 and 123.8 lb RGC, and GNC 300 specimens at 153.2 and 160 lb RGC. The recorded spreads also differed between examples.[3]
These are specimen measurements from a collector's table, not factory tolerances or a universal conversion between the GNC labels and other brands. The original table preserves the mounting-depth and spread notes alongside the ratings.
References
- Iron Man magazine, Ultimate Power Grips, September 1, 2011. ↩
- GNC Grippers 200, 250, 300, The GripBoard, February 2012. ↩
- Jason Steeves, My RGC Ranked Grippers, collection measurements, May 2012. ↩