It’s what makes No-Flush™ urinals work! BlueSeal® is a long lasting and biodegradable trap seal liquid that has a specific gravity lower than water or urine. Therefore, it remains in the trap for an extended period of time with urinal use (small amounts do get carried out with each urinal use), or BlueSeal® remains indefinitely in the trap with no use, sealing trap odors. BlueSeal® has zero evaporation at 100° F and does not freeze above -70°. The no freezing feature allows facilities to eliminate or reduce urinal winterization costs. Commercially available cleaners will not harm the BlueSeal® in the EcoTrap®. BlueSeal® is simply added in three (3) ounce portions into the urinal EcoTrap® via the PortionAid. Please follow instructions on bottle.