Summit GEO SH-130 and GEO SH-140 are low ash, balanced medium TBN gas engine oils manufactured from the finest synthetic base oils to optimize performance. Summit GEO SH-130 and GEO SH-140 are recommended for lean- or rich-burn service in two-stroke and four-stroke gas engines, naturally aspirated to turbo-charged. They are formulated with the latest in gas engine oil additive technology comprised of superior anti-wear and anti-scuff agents, oxidation & nitration inhibitors and detergent-dispersants to neutralize corrosive gas components, provide excellent protection against valve component recession or beat-in and disperse combustion by-products for improved gas engine cleanliness and low combustion chamber desposits.