The Nikon WG-AS1 Water Guard is designed to maintain the D3's high level of dust and water protection, when used in combination with the SB-900 Speedlight flash unit. The WG-AS1 clips onto the flash unit's foot, creating a shield against dust and water.
Reviews Nikon WG-AS1 Water Guard for D3 Camera's Hot Shoe when used with SB-900 Flash