Nice TYCO or Mattel Speed Controllers. These TWO (2) Controllers, will work on just about every Electric Slot Race Car set TYCO or Mattel ever made. GREAT to be able to CONTROL EACH LANES MAXIMUM SPEED!****NOTE: 3-SPEED CONTROLLERS ARE MADE FOR 4 OR 6 D-CELL BATTERY BOX, RACE SETS. They are intended to run on around 4-8 volts of input. When they are connected to a typical transformer (12-24V) they act more like an on/off switch, rather than to control a range of speeds. Also, under a transformer load, their life will be dramatically decreased may quickly burn out. Please ALWAYS USE A SURGE PROTECTOR GROUND FAULT FOR ANY POWER SUPPLIES. Using a BATTERY BOX for a power source is cool though! It allows the track to literally go anywhere, typical slot cars will run just fine, albeit slower, cars pickup shoes will last much longer due to the reduced friction. On any TYCO/Mattel race set up, you could put the BATTERY BOX ON ONE LANE AC VOLTAGE ON THE OTHER. Simply use two terminal tracks any where you'd like. Plug a transformer typical controller into one plug a battery power box a 3-speed controller into the opposite lane, of the second terminal track. Also they work well to break in motors by setting up a short oval letting a new car go around for awhile. Sold as is. Buy with confidence please check out my other offbeat slot car related items. I will pack your item(s) well try to ship promptly. Descriptions are very accurate; No Returns. PLEASE ASK BEFORE YOU BUY IF YOU ARE UNSURE. Glad to combine shipping when practical. We ship promptly professionally. We happily combine orders refund any excess s/h immediately upon shipping. We can always provide tracking. ************** From I Only ship U. S. Postal Service PRIORITY MAIL TO THE USA due to previous 'lost' packages. ******************* I apologize for any inconvenience, but; Due to previously lost packages: ALL INTERNATIONAL Shipments Only Ship by U.S. Postal Service, GLOBAL EXPRESS. Very Fast Delivery Absolutely, Positively Guaranteed to arrive. I charge $2 or less for expert handling/packaging, actual shipping. I ship out of the country almost daily. Please refer to my feedback, rating or time selling HO slots for assurances of a good honest deal. happy motorin' thanks S'lots from bob at SlotCarCentral 2201 Teall avenue Syracuse, NY 13206. Questions or issues gladly taken care of. phone 8 days a week, 25 hours a day. bob at slotcarcentral.com We Know H.O.