Hastings STD Piston Ring set Moly fits Ford Barra 5.4 220 230k F150 F250 RM RN F | eBay
Jeep 4.0L Piston Rings - Moly by Hastings (2M667)
Speedmaster PCE306.1039: Plasma Moly Piston Ring Set | 4.040 in. Bore | Top Ring Thickness: 1.500 mm | Second Ring Thickness: 1.500 mm | Oil Ring Thickness: 3 mm | Zero Gap - JEGS High Performance
The Material Details & Evolution of Piston Ring Technology