1/32″ thick reusable fiberglass reinforced silicone gaskets. You can tighten them down and they won’t squish out like regular silicone. Available for rocker covers, oil junction block, rockerspindle covers, tacometer, timing cover, sump breather, JS reed valve breather housing, tranny cover, intermediate tranny, tranny inspection and Atlas magneto. High heat tolerant and oil tight. Sealer unnecessary.