480310E UView Eco-Twist™ Leakguard™ Injection Kit - What is LeakGuard? Leakguard permanently and safely seals A/C leaks in both rubber and metal components. The only A/C Sealant available that is Certified to meet SAE J2670 Standard! Unlike other A/C sealants, LeakGuard is an oil based sealant that does not have any of the dangerous side effects. It will not harden, crystallize, clog the A/C system or harm the recovery equipment.