Dr. Diffs shipping cost.

I used a square cut injector Oring off of a 70s Ford diesel tractor. We worked on tractors in our shop.
It's all a money game. Keep the price on the item low for the sale, then add extra on the shipping. Kinda like what the cable companies been during for years. $59.00 then after other expenses and fees, $99.00. Same for hotel rooms and hospital billings.