They went over all the spec and different options for my engine. Arrived in the time they stated and haven't sent mine back since I just finished swapping today, but so far the best eBay automotive company to work with. Great product, everything the promised and my car went from 120, 40, 60 and 90 psi per cylinder because of a few bent valves to 187-190 for all four. Super happy. Thanks! My Dad will be using you guys for his Toyota 4Runner!