The Kartboy shifter lock reduced left-to-right play in the shifter of the 2015-2021 WRX, to give a tighter shift pattern with less slop. Installation is easy -- we installed one on our own shop car in about 20 minutes.

Some products of this type are made of metal, which can causing clanky noises when the shifter comes into contact with the stop. The Kartboy parts is made of a very strong glass-reinforced nylon, so it is nearly silent.

Here's a helpful install video:

 Fits all 2015-2021 WRX with manual transmission.