Roto Grip · HP4 line
The Roto Grip Perfect Gem is an asymmetrical solid bowling ball from Roto Grip's HP4 line, released in October 2026. It has the ER1 Solid coverstock and the Gem AI weight block, finished at 2000 Grit out of the box. At 15 lb its RG is 2.49, with a differential of 0.057 and a PSA of 0.017.
Among the 65 balls here with a 15 lb version, its RG is low, so it revs up early, and its differential is high, for more flare. Its reaction ratings suit it to heavy oil and medium to long patterns in fresh conditions, with an early hook, a smooth turn at the breakpoint and high flare.
Specs
Details
- Coverstock
- ER1 Solid
- Weight block
- Gem AI
- Core
- AI
- Symmetry
- Asymmetrical
- Factory finish
- 2000 Grit
- Durometer
- 73-75
- Flare potential
- High
- Color
- Pink/Rose/Onyx
- Release date
- 10/02/26
Reaction
- Flare Potential11
- Ball Shape1-4
- Hook Length1-3
- Oil Volume8-11
- Pattern Length7-11
- Lane Condition1-4
Tech specs
| Weight | RG | Diff | PSA |
|---|---|---|---|
| 12 lb | 2.59 | 0.029 | 0.008 |
| 13 lb | 2.57 | 0.032 | 0.01 |
| 14 lb | 2.52 | 0.056 | 0.016 |
| 15 lb | 2.49 | 0.057 | 0.017 |
| 16 lb | 2.49 | 0.055 | 0.017 |
Balls most like it
Available balls closest to the Roto Grip Perfect Gem on the six reaction ratings; 100% is an identical reaction.
900 Global Viking Conquest Solid92%
Roto Grip Wicked Gremlin Solid89%
Storm Alpha Crux Solid88%
Storm Ion Max Solid87%
Storm Phaze II Solid85%
900 Global Vengeance Solid85%
Storm Bionic Hybrid75%
Storm Ion Max Pearl Pearl72%
Related balls
The rest of Roto Grip's HP4 line.
