Brand New ProComp Set of 8 File Back Moly High Performance Piston Rings, 4.030" Bore, Metric (Part #4588). These piston rings are designed to stand up to the rigors of racing and high performance street use while providing long lasting life. File back moly piston rings fit matching bore sizes while allowing for custom filing to achieve proper end gap. Features: Plasma-coated, barrel-shaped, ductile iron top rings that seal against blow-by when the piston rocks in its bore. Tapered secondary rings that seal against the oil control rings upper surface for excellent oil control. 3-piece oil rings with stainless steel expanders that provide accurate tension without the loss of any horsepower. Sold in sets of 8. Specs: Piston Bore Size: 4.030" Top Piston Ring Facing Material: Plasma Moly Top Piston Ring Material: Cast Iron Top Piston Ring Thickness: 1.5 mm Middle Piston Ring Material: Cast Iron Middle Piston Ring Thickness: 1.5 mm Oil Piston Ring Material: Stainless Steel Oil Piston Ring Thickness: 3 mm Quantity: Set of 8
