Vantec RDFR21 Speed Controller A very compact dual-channel speed controller for smaller bots. This is a good choice controller for the beginner builder who is using motors that draw low current
Vantec RDFR22 Speed Controller One of the most popular models for Combat Robot use. This is also a very compact dual-channel speed controller for smaller bots.
Vantec RDFR23 Speed Controller This is a great controller if you're looking to move into larger robots. Due to it's higher power handling, it is a good choice for robots 60-100 lbs.
Vantec RDFR33 Speed Controller When you're intending to power your bot with some of the more current-hungry motors out there, it's time to beef up to a larger speed controller. The RDFR33 is a whole new design over the RDFR2x series.
Vantec RDFR36E Speed Controller Now we're getting serious. The RDFR36E has a thick, extruded aluminum case to assist in heat dissipation, and can handle much more current than the some of the other models.