Description:RennTech HHT (hand held tuner) allows you the unlimited ability to switch between tuned and stock ECU programming and requires no ECU removal. RennTech proprietary tuning module stores both the RennTech tuned file and your vehicles stock file. The module plugs directly into the OBD2 port and delivers the file you choose directly to the ECU. Programming takes only a few minutes and the vehicle can be reflashed at any time as many times as you wish.RennTech has been at the forefront of ECU tuning since electronic engine management started to show up in vehicles during the mid 1980s! Our experience, countless hours of in-house research, development and exhaustive testing ensure that our proprietary ECU upgrade offers incredible performance gains and rock solid daily driver reliability.RennTech tuning software for Mercedes offers significant gains in horsepower and torque across the vehicle's entire power band. By modifying ignition timing and throttle mapping, optimizing air-to-fuel ratios, increasing the engine's rev limiter and modifying boost mapping for turbo-charged vehicles, RennTech performance software unleashes the true potential of your Mercedes.With the RennTech ECU Upgrade the W205 - C 43 AMG Sedan gains up to +25 HP and +42 LB-FT, based on power numbers measured by RennTech. Please note that the Mercedes M276 engine performance when measured obtains higher numbers than rated from factory. The maximum power number reached with the RennTech ECU Upgrade for the W205 - C 43 AMG Sedan is 400 HP and 440 LB-FT.Attentions:Mercedes M276 engine performance when measured, obtains higher numbers than rated from factoryPower gains are calculated with stock numbers measured by RENNtechCrank Performance Numbers are calculated with a 17% Drivetrain loss on 4MATIC vehiclesOur numbers will be dependent on conditions and fuel quality. 91+ Octane gasoline is mandatory with this Performance PackageFeatures:Gains up to +25 HP and +42 LB-FTLong-lasting and driver reliabilitySignificant gains in horsepowerIncreases the performanceSignificant gains torque Increasing the engine's rev limiterIncredible performance gainsStock Performance:362 HP @ 5,500-6,000 RPM; 384 LB-FT @ 2,000-4,200 RPM375 HP @ 5,600 RPM; 398 LB-FT @ 3,300-3,600 RPMModified Performance:400 HP @ 5,450 RPM; 440 LB-FT @ 3,250-3,600 RPM Vehicle Fitment:    2015 Mercedes-Benz W205 C43 AMG Sedan 2016 Mercedes-Benz W205 C43 AMG Sedan 2017 Mercedes-Benz W205 C43 AMG Sedan 2018 Mercedes-Benz W205 C43 AMG Sedan 2019 Mercedes-Benz W205 C43 AMG Sedan Note:Images are for representation purpose only and may differ depending on application.