STP® Extended Life Antifreeze/Coolant is a long service life product based on a proprietary organic acid technology (OAT). This ethylene glycol-based product is free of silicates, phosphates, borates, nitrates, nitrites, and amines. It protects coolant system metals against rust and corrosion and provides excellent high temperature aluminum protection. It is fully compatible with other similarly formulated OAT coolants and is recommended for use in newer model foreign and domestic cars and light duty trucks. When properly diluted and added as an initial fill, this coolant provides up to 250,000 km (150,000 mils) or 5 years service life protection in automotive applications.

For best results, Extended Life Antifreeze/Coolant must not be mixed with conventional high pH, phosphate, borate, or silicate containing coolants. STP® Extended Life Antifreeze/Coolant has a distinctly orange colour to help differentiate it from conventional engine coolant, which is typically, but not always, green. While deleterious effects are not expected to be significant, the mixing of conventional coolants with STP® Extended Life Antifreeze/Coolant will result in a lower than expected lifetime (change-over intervals)