I believe them Great Dane's come fitted with one! But that may be just the movie star type. Im sure twilbanks can confirm that.
Always have to drag me into it....
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If you run one on a Dane, be sure to tie it on haning underneath their stomach.... if you put it on their back or head, they are too tall to get good video of the hog they are baying....
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gonna have to put it round their knees if you take em to florida, them midget hogs will run under their legs
if you want a small camera thats waterproof try this one, its a dive camera but its small and water proof and you can clip it to their collar
http://www.leisurepro.com/prod/AQUESC.html?srccode=cii_9324560&cpncode=21-132820890-2