Roto Grip Gem vs. Roto Grip UFO Alert

Compare the specs of the Roto Grip Gem and Roto Grip UFO Alert side by side in the ball comparison table below. To view the full bowling ball review for one of these balls, click the ball name link in the table below.

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Roto Grip Gem
Roto Grip UFO Alert
Ball NameGemUFO Alert
Cover NameMicroTrax Solid ReactiveeTrax Hybrid
Cover TypeReactive SolidReactive Hybrid
Box Finish2000 Abralon1500 Grit Polished
ColorCitrine / Ruby / AmethystPurple Solid / Emerald / Teal
Core NameDefiant LRGE.T. (Equalizer Technology)
Core TypeAsymmetricalAsymmetrical
Total Diff.0.0530.054
Int. Diff.0.0160.016



Back End

Total Hook

Ball Tester Ratings

Bowling Ball Comparison Graph

The graph below shows a visual comparison of the selected balls. Hover over each colored circle in the graph to see that ball’s name and ratings. Click a circle to view that ball’s full review.

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