These brackets raise your Porsche LWB seats approximately 1" in the front, reclining the seat. One order provides brackets to adjust ONE seat. For owners who feel the stock seat position is too upright. Installation instructions are supplied. Raises your Porsche Carbon Fiber LWB seats approximately 1" in the front The 718 GT4 has less rearward clearance. Due to the seat being reclined back, the seat will interfere with the firewall if it adjusted all the way back and lower than the highest setting. TO PREVENT DAMAGING YOUR SEAT, MAKE SURE YOU HAVE REAR CLEARANCE BEFORE LOWERING THE SEAT HEIGHT. Seat at highest position: 8.5" of forward to back movement (full range) Seat at middle height position: 7.5" of forward to back movement (12% less) Seat at lowest position: 6.5" of forward to back m.