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Actress Eva Mendes tested her dog's shock collar on herself before putting it on her beloved pet to make sure the device was safe for her pooch.

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The "Hitch" star invested in a special collar to prevent Hugo, her Belgian Shepherd, from harming smaller animals.

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However, she was so concerned the gadget would hurt her pet, she tried it out on her own arm first -- and was surprised by the powerful jolt it gave out. Mendes tells talk show host David Letterman "All he (Hugo) wants to do is prove his love to me, you know, all he wants to do is kill for me. It's so sweet. (But) I'd feel terrible if he hurt a little thing so I try to get in there and I use - people always get mad at me for this - but I use a shock collar on him and I have the remote. But I've tried it on myself at all levels. I swear!...

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"I do not do it on my neck. I tested it on my arm. It's more than a tingle, it's way more than tingle. Oh, remember when we were kids and we had that jokey thing where you shake hands and ahh that thing (hand buzzer)? It's like that but intensified the higher you go with the levels."