Engadget is reporting that according to their reliable sources, Best Buy is prepping to give away free covers from invisibleSHIELD specifically designed to attach to the side antenna on the iPhone 4. The invisibleSHIELD 4FIX from Zagg is cut specifically for the sides of the iPhone 4, making it a less bulky option than a complete case for those who want to improve reception on their handset.

This cover is made from military grade and prevents scratches. Also from the leaked picture, you can see that the 4FIX cover has been independently tested by antenna experts, and have been proven to enhance reception on iPhone 4. The 4fix covers comes in 7 separate pieces and when applied to the iPhone 4 will leave space for the volume, the SIM card tray, lock buttons, and the port on the bottom of the iPhone.

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