Price with shipping included for adaptor kit is USD $ 220.29 and keep in mind there are two adaptors and two valves, not just one as usual. I don't know how much HKS valves are but you can check yourself with this part number 71008-AK001 Those adaptors are made from aluminium and it looks like they are machined so I imagine that's why they are expensive. Everything is doubled with 3.3T engine.