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They said I can’t.
That is why I must.

The odds have been stacked against me since the day I was born. No one expected me to succeed. Sheer logic wouldn’t allow them to accept the magnitude of my capabilities. But the doubters. The naysayers. They’re what fuel me. I do not fear the odds, the expectations or the logic. For the second you send me down the lane, I will defy them all.

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I may look menacing on the outside. Truth is, deep down, I’m even more tormenting than you thought. Pins quake at the mere mention of my Paragon™ core technology. My strong midlane roll and huge, sweeping backend hook hits so hard that after I’ve come through.


Whoever said that what’s on the inside is all that matters didn’t have a cover like mine. It’s called MicroBite™ Technology, and it’s the latest and greatest that science has to offer. More strength and more texture than most know what to do with. Oh, I’m gonna hook. And nothing out there’s gonna stop me.


You can put as much oil out there as you want, Mr. Lane Man. I’m gonna bite through it like a knife through warm butter. Need I remind you of my MicroBite cover? You set ‘em up, I’ll knock ‘em down. Any lane. Any oil. Anywhere.


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Defiant™ Bowling Ball Technical / Specs

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Coverstock Name MicroBite™™
Coverstock Style Solid
Coverstock Type Reactive
Weight Block Paragon™
Color Blue/Purple/Black
Finish 3000 Abralon®
Finish Method Can be polished
Durometer 73-75
Flare Potential 7+ inches/High
Weights 12lbs - 16lbs
Release Date 01/10/12


Weight Radius of
Differential PSA Differential
16 2.49 0.052 0.017
15 2.49 0.054 0.017
14 2.52 0.053 0.016
13 2.57 0.032 0.010
12 2.59 0.029 0.008

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Lane Comparison

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to Glory.

Compare the shot shapes of any two balls in the current Roto Grip lineup by choosing your style, any lane condition and the two balls you want to see go head-to-head.

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Balls to Compare


Pennsylvania State Men's All events Champion Using A Defiant
won the PA men's states all events title in Erie, PA this year.
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279-757 first time out!!
279 with Defiant 757 with Defiant/Defiant Edge
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Career high of 279!
I bowled a solid 279!! Every shot was deep in the pocket! The messenger missed the 10 pin in the 5th....
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Honor Scores

300 Game
Adam Morse
Waukee, Iowa
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300 Game
Adam Morse
, Iowa
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300 Game
Andrew Miller
Carmel, New York
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In the News

Indiana's Randy Bockelman Fires 897 with Defiant...
897 with Roto Grip Defiant...
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