Hydraulic Flat Tappet Lifters (16)Designed and manufactured using the tightest tolerances in the industry for ultra-precise constructionOil metering band is milled to exact depth to prevent too much oil from being delivered to the top of the engineFace of the lifter is ground to precise radius for proper break-in and guaranteed longer lifeApplicationsOldsmobile V8 260-455 Specifications .842" Diameter - 97g Weight - 2.05" Seat Height.