The BlackZon Slayer has been rebranded to Blackzon Slyder but the product remains the same! Batteries make everything go in RC racing. The BlackZon Slyder Battery Pack (Li-ion 7.4V, 800mAH) with Dean Plug is a certified Blackzon Slayer/Slyder RC Car. Li-ion batteries have one of the highest energy densities of any battery technology providing more racing power than any other RC batteries on the market.