If you received retro bars with the slit at the bottom, AND you want to buy the SCS, then you will have to just cut 2 inches off the bottom of your bars in order to maintain the height you were at with your bars, and your bars will come usable/compatible with the SCS.rayan simian said:wait, i got retro bars like a few days ago and they didnt have the standard compressions system options. i will be buying a standard compression system to use with these bars though. what do i do now? the bar dimensions i ordered with are 21x15. can you make them custom to the scs compression please?