At Adapter Kings our wheel adapters are made from the highest grade aircraft aluminum. This aluminum is used in several different military applications. We feel if this aluminum strong enough to protect our country then it is strong enough for your ride. We know your ride is important to you that is why we use the best aluminum on the market. Each of our adapters come with standard 12mm x 1.50 SAE approved, OEM quality studs that our pressed into the adapters. Except for some 8" plate adapters which come standard with 14mm. All other stud sizes incurs additional charges. Some common studs are listed. Also all our wheel adapters are priced individually but the minimum purchase quantity is 2 wheel adapters. Please call if you have any questions. Each one of our adapters are custom built for your car with the best CNC equipment in the industry. We will custom build your adapter in 1 to 4 business days. Standard ground shipping takes 2 to 6 business days. You could receive your custom built adapters in as little as 4 business days.