"Three anti-lights" is a marketing abbreviation that refers to preventing three things at the same time: water, dust, and impact. The problem is that buyers often confuse these three points, and specifying IP67 when IP65 is sufficient is an expense that costs a lot of money but buys nothing.

According to IEC 60529, the first digit of IP is solid and the second digit is water. IP65 means that dust is completely penetrated and resists spray water from any direction. IP66 elevates the water test to strong water spray. IP67 means that the enclosure can withstand short periods of immersion, typically 1 meter of water depth for 30 minutes. For parking lots, workshops, or covered loading and unloading platforms, IP65 or IP66 is usually the correct specification. The high premium for IP67 is only cost-effective in flushing areas, tunnels where water may enter, or on lamps installed below the water table.

Collision avoidance performance is another set of standards, namely IEC 62262. IK08 corresponds to a 5 joule impact and is a reasonable bottom line for industrial locations (with ladders and cart activities). IK10 corresponds to 20 joules and is suitable for stadiums, public trails, and any location where a ball or vehicle may hit it.

The third protection is often ignored: shell material. Impact resistant polycarbonate diffusion covers can still yellow and crack under years of ultraviolet light; coated steel or aluminum casings can corrode in wet processing workshops. Please ask for the materials of the housing and diffuser cover at the same time, and make sure that the sealing ring is silicone, not a cheap elastomer that will harden and leak in two or three years.