Panasonic 4 GB Hi Speed 15MB/s SDHC Class 4 Memory Card with Water/Shock/Magnet/X-Ray Proof RP-SDN04GU1A Improved construction to withstand everyday conditions: Waterproof, Shockproof, Magnetproof, X-ray proof Up to 15MB/sec transfer rate Content/media protection (write protection switch) Extreme operating temperatures (-25C ~ 85C) Class 4 speed specification: guaranteed 4MB/sec transfer rate