I bought this to fix a leak in one of the spark plug tube seals on my '00 (AP1) S2000. The drain pipe o-rings are *very* tight. Ideally you'd install them with a hydraulic press, but I don't have one, so I ended up using a block and rubber mallet. At least they are reliable and I'm not worried about them loosening in the valve train. The fit around the tubes is good. The main valve cover gasket is tight enough not to slip out of the groove during installation, but could be tighter. After tightening the cap to the repair manual specifications using the replacement hardware from this kit, I can confirm that the cap is not leaking after about 20 miles of test driving. Overall the kit did what I needed, but I feel like it could have been a bit simpler and better quality.