Safe d-Solv HD contains all natural Dipentene, which is derived from natural terpene extracts. Effective on grease deposits, tar accumulations, oil stains, dirt, and grime. Also ideal for use as emulsifiable parts washing solvent. Contains zero percent d’Limonene yet has all the strength and power associated with d’Limonene. This product is considered the “sister” product to d’Limonene based, Safe Solv 378.