Champion Spark Plug RV17YC #25 #25S Replaces: 912 RBL16Y RBL17Y RBL87Y BPR4FS UR4 UR45 1127 6630 6945, SELECT: Box or Shop Pack Champion copper cored center electrode with triple coated shells, this eliminates the need for the use of anti-seize compound during installation by providing the best corrosion protection of any spark plug in the industry. The Champion Copper Plus core with Zirconia enhanced insulator spark plug features a copper core electrode that provides increased conductivity and heat control while delivering good overall wear characteristics. Copper core center electrode allows for accurate control of the plug's heat range, optimizing the plug's performance and adding to the longevity of the spark plug. The spark plug is designed to withstand high operating temperatures. Plug: #25 #25S Model: RV17YC Thread size: 14 mm Reach: 0.460 in Wrench Hex Size: 5/8" in Spark plug seat: Tapered Installed Height: 2.3 in Box Pack: MPN: 25 UPC: 037551000265 Shop Pack: MPN: 25S UPC: 037551712397 Shop Pack plugs are shipped wrapped in bubble wrap. Purchase is for one spark plug. USA domestic shipments are shipped USPS Ground Advantage Mail with Tracking When buying different variations from the same or similar listings, the lowest shipping cost is obtained by buying the total number of units wanted from 'One Variation' and then leaving a message within your order defining what items you want to receive and the number of each item you want to receive. The number of items requested cannot exceed the number shown as being in stock. This stops from restarting the total weight summation for each variation. The message link is on the same page where you select method of payment.USPS postage cost is based on total weight and zip code. The cost breakdown is shown before payment is required and the discount for multiple purchases is shown as a separte credit in the list.