Solid/Mechanical 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 lifeApplications: Ford Big Block V8 FE 352-428 (Shell Type) Specifications .875" Diameter - 61g Weight - .46" Seat Height (Shell Type).