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No matter the condition of your 2005 STS, OPGI offers five Proportion Valve related parts to boost performance and get your 2005 STS back on the road. Choose from trusted brands like CPP and Russell, with prices ranging from $14.99 to $108.99, all backed by our Price Match Guarantee. With OPGI’s 60-day return policy and thousands of verified reviews, you can shop confidently for your 2005 STS restoration. Enjoy fast shipping directly to your home, or visit our Southern California Showroom & Warehouse to see our Proportion Valve related parts in person.
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