mousetrap powered car kit

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mousetrap vehicle kits | item number: KMTV375DF

Lock-Tight ™

Online Price: $34.95

Availability: This item is currently in stock

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Lock-Tight is the most advanced and the easiest to operate braking system available. Lock-Tight has a wing-nut that travels along a threaded axle and then wedges itself against the frame causing the racer to come to an instant stop. Lock-Tight comes ready-to-assemble with pre-cut and pre-drilled parts so you can be ready for action and racing on the same day. As with all our kits, Lock-Tight comes with step-by-step instructions that are filled with tons of top secret performance tips and tricks that have been developed exclusively by Doc Fizzix so that you will have all the information you need to make Lock-Tight a winner.

Why Doc Fizzix:

At Doc Fizzix, we have been designing, making, and building mousetrap powered cars for more than 30 years. Unlike any other mousetrap vehicle kit you will find on the market today, each of our kits has been designed and tested over and over again to insure your success. We use only the best quality parts and components in our kits. We have been featured multiple times in books, magazines, and national aired programs. We wrote the very first book devoted exclusively to the building of mousetrap vehicle selling more than 200,000 copied world wide. Our kits are used in more schools across the country than any other brand. Mousetrap powered cars and vehicles is our specialty.


  • Top secret braking system
  • High-grip tire treads
  • Light-weight balsa wood
  • Brass tubing axles
  • 12-inch brass lever arm
  • Pre-cut and pre-drilled
  • Doc Fizzix's easy-wind, snag-free propulsion system
The Lock-Tight can be assembled in less than 45 minutes for most first time builders and when finished can be set to travel and stop between 1-20 meters. Lock-Tight comes with a 12-inch lever arm making Lock-Tight a good long-distance vehicle without the need for adjusting the lever arm length once assembled.

How it works:

Lock-Tight's braking system uses a special wing-nut that travels along a threaded axle until it lock tight against the frame of the vehicle causing the Lock-Tight to come to an instant stop. Setting the braking system is simple and easy: just place Lock-Tight at the finish line with the wing nut in the lock position, roll the vehicle back to the start line, and now you are ready for racing. Rolling Lock-Tight from the finish line to the start line sets the wing-nut in the exact position needed. Lock-Tight also comes with two rubber treads that are designed to increase the stopping traction helping the racer to come to a stop without skidding.

As with all our top mousetrap racer kits, Lock-Tight includes our "easy-to-wind" and "snag-free " string release system that will not tangle or snag for increased performance, a technique developed exclusively by Doc Fizzix.

Travel distance:

  • 1-20 meters (1 - 65 feet)* Adjustible stoping distance

Kit includes the following:

  • Victor mouse trap
  • Kevlar high-tech string
  • Pre-cut and pre-drilled balsa wood frame
  • CD wheels
  • Tire treads
  • DVD wheel adapters
  • Brass tubing axles
  • Thrust washers
  • 12" lever arm
  • Top secret braking system
  • Doc Fizzix's easy-wind, snag-free propulsion system
  • Step-by-step plans with performance tips and tricks

Tools required:

  • Needle-nose-pliers
  • Super glue
Size : length = 21 inches, width = 6 inches, lever arm = 12 inches.

Weight : 6.9 oz.

mouse trap car mouse trap car mouse trap car *Kits require assembly, actual results will vary, glue and tools not included.

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Phone Hours: Mon. - Fri. 10:00 a.m. - 5:00 p.m. (CST) - 866-362-3499 (US only) or 512-218-0454
Doc Fizzix Products, P.O. Box 5507, Round Rock TX 78683, U.S.A.