Available in packs of 6 or 70. AMSOIL antifreeze test strips have two different pads on them and test ALL coolant colors. The lowest reports the freezing and boiling (under pressure) protection level. The upper pad reports the pH level and shows a pass/fail area. No other testing is recommended or required. The test strips are the only way a mixture of ethylene glycol and propylene glycol can be checked for freeze protection.