3 hr Non Maintained Atlantic. Atlantic is a highly versatile internal or external bulkhead with a number of innovative features. It is IP65 rated and vandal resistant, the diffuser can only be removed by use of a tool. Careful optical design also provides excellent photometric performance, installation time is minimised by use of a plug in geartray and self locking clip on diffuser. IP65 rated. Snap on self locking diffuser. Vandal resistant.