Powerball's PowerGripper Metal Series, sold by RPM Power, consists of fixed-resistance torsion-spring grippers with colored metal handles. It is distinct from the company's gyroscopic Powerball exercisers and adjustable PowerGripper products.[1][2]
Models and identification
RPM Power lists eight Metal Series strengths. Each uses a different handle color:[1]
| Model label | Handle color |
|---|---|
| 50 lb | Pink |
| 100 lb | Purple |
| 150 lb | Blue |
| 200 lb | Red |
| 250 lb | Black |
| 300 lb | Silver |
| 350 lb | Gold |
| 400 lb, “The Hulk” | Green |
The manufacturer describes stainless-steel springs and a diamond-pattern gripping surface. Its 400 model is described as slightly larger than the other models.[1]
Sets
The seven-piece set contains the 50 through 350 models and a display stand. The green 400 is a separate addition to the range, not one of those seven grippers.[1][2]
Independent rating records
In March 2025, Matt Cannon published measurements collected when Cannon PowerWorks stocked Powerball box sets. His figures included a 300-model average of 144 lb RGC, with measured examples from 130 to 152 lb. The 400 averaged 196 lb, with examples from 176 to 209 lb.[3]
These are historical measurements of sampled grippers, not guaranteed specifications for a newly purchased example. They also demonstrate that Powerball's advertised model numbers and RGC ratings are different scales. The original discussion preserves the complete measurements without requiring a duplicate ratings database here.[3]
The same discussion contains an owner's observations of a seven-piece set, including measured handle spreads of approximately 67 to 71 mm. Those measurements describe that owner's set rather than a manufacturer tolerance.[3]
References
- RPM Power, Metal Grip Strengtheners, manufacturer model and color descriptions. ↩
- RPM Power, Metal Grippers 50-350lb, seven-piece set. ↩
- Matt Cannon and mcalpine1986, Power Gripper: Metal series grippers set, The GripBoard, March 17, 2025. ↩