The Answer:
Whether or not you've heard of the actual rating, IP ratings are becoming more attractive to consumers since they are applied to cell phones. Everyone wants to know what will happen to their phones if they were accidentally dropped in water. Either them or the phone! We know we do. We also have a baggie of rice labeled "Phone Rice" standing by, waiting to work a miracle after forgetting a phone in a back pocket. The ranking applies to a wide variety of devices, enclosures, and equipment including Christmas light bulbs!
All of the Christmas Light Source Minleon LED bulbs are IP65-rated. That means they've passed tests for dust and water penetration.
They are dust-tight and water-resistant as tested with a low-pressure water spray from all angles. They are not waterproof. They can not be submerged. That shouldn't be an issue since it is a terrible electrical hazard to do so.
Ultimately, IP65 means that Minleon LED bulbs will withstand dust, dirt, and water during the Christmas season. That's good news for everyone.
More info on IP65
IP: Acronym for Ingress Protection
6: This is a measure of how much dirt and dust can get inside a device or enclosure. The scale ranged from 0 (no protection) to 6 (sealed shut). A rating of 6 indicates that our bulbs have been tested and shown to be totally dust tight. They have been rated for complete protection against dust and other particulates, including a vacuum seal tested against continuous airflow.
5: The second number is a measure of water protection. A 5 rating means a device is tested with a .25-inch low-pressure jet of water from 3 feet away at different angles. The total scale ranges from 0-6 or from no protection to protection from a high-power nozzle from all directions and limited submersion at level 6.