Copying SD cards on mass can be a good business tool - for example why distribute photography related information on anything other than SD Cards? You could provide course literature or business card info all on an SD card - they are cheap, much longer lasting than cd's and quicker to read and write too - copying sd cards in bulk is even quicker!
SD Card Duplication
If you are copying more than 2 sd card's at a time it might well be worth investing in an sd card duplicator - it will take 1 sd card and duplicate it in bulk, saving you the time of putting sd cards in and out of slots, copying etc etc.
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SD card to SD Card copying?
Even if you are just backing up an sd card, perhaps saving your travel pics to another card you are going to send home to be safe - you can get 1 to 1 sd card duplicators at great bargain prices too!
Typically you can get sd card duplicator boxes in 1 to 15 or 1 to 10 - these take a single sd card (usually up to 16, 32 or 64 gb in size) and copy it to 10 or 15 other blank sd cards at the same time - some machines format cards first, others simply overwrite all data present on the SDCard
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Write Speeds
Unlike the confusion that used to surround duplicating cds and dvds SD cards are pretty universal in speed - most are fast! haha. no but compared to cds seriously duplicating sd cards is very fast business.
Thanks for visiting - if there isn't many sd card duplicators above then check back later - theres usually a good selection about!