This product is a set of (8) NOS Mopar OEM spark plugs. With vintage part status and OE/OEM part number 3755840, these spark plugs are a reliable and authentic choice for classic car enthusiasts looking to restore or maintain the ignition system of their vintage vehicles. Crossover number is P-557P. The outer cardboard package is well worn, but the plugs are pristine! These plugs are for '75-'83 slant six mopars. Note, the mopar stamp on the plugs. My husband and I had a machine shop. He passed, leaving me lots of shelf inventory to sell. This is part of that inventory. Shipping via USPS ground advantage. I ship out same or next day. And I will always combine shipping!! Be sure to check out my store often, as I am gradually pulling parts off the shelf and listing them.