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Underload Trainer Bat

RSP (by ProBats)

The Pro Bats Trainers have the exact look and feel of an actual bat. Most importantly, the weight distribution exactly replicates that of a normal bat. So throw out the donuts and broom handles. Improve your game the ProBats way.

There have been numerous studies conducted on the benefits of utilizing the principles of overload and underload training to increase strength, and most importantly bat speed.

The Underload Trainer is available from a -5oz weight differential up to a -9oz and research increased bat speed. The underload helps develop a hitter's fast twitch muscles to move at maximum speed while concentrating on the exact muscle group and in the exact motion that is used in a game.  

Research also shows that to obtain optimum results the player should replicate the actual skill as closely as possible. The Pro Bats Trainers have the exact look and feel of an actual bat. Although live balls should not be hit with these bats, your players will gain virtually the same results by dry swinging, which will obviously greatly extend the life of your bats.

Regular price $99.95
Regular price $109.95 Sale price $99.95
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Shipping calculated at checkout.

Manufacturing Turnaround Time

All custom bats are made to order. On average, custom bats require up to 2-3 weeks manufacturing prior to shipment. During busy portions of the year, manufacturing may take up to 4-6 weeks.


Orders ship via USPS or UPS Ground depending on delivery location when selecting Standard Shipping.

Please Note: If Overnight or 2nd Day Shipping is selected, the bat will ship after it has been made, not the day or two after your order is placed.

Care Instructions

To avoid any unnecessary damage, it is important to properly care for your bat. Throwing your bat even on grass or dirt, or tapping against cleats or other surfaces. The repetitive impact can cause chips, cracks or splits which can get worse over time.

It is best to avoid storing your bat in excessive conditions. Excessive heat, moisture or dryness can make your bat brittle. 

Only hit leather baseballs. Do not hit dimple ("cage") balls, weighted balls, or anything other than a leather baseball made to meet the specifications of game play.

This isn't specific to ProBats, but to all quality wood bats.

  • MLB Premium Grade Wood

  • Ink Dot Tested & Certified

  • Handcrafted in the USA

  • Professional Steel Pressed

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