(Quoted from Aaron Montgomery and Printwearmag.com. Full article here.)

One drop of ink, one misplaced thumbprint, one pinhole can ruin a T-shirt and cost you money. A spot-cleaning gun can save the shirt and your production run. Besides the gun, a device with a screen and exhaust (commonly sold with spot-cleaning guns) will help to hold the shirt in place and to dry the spot-cleaned area of the garment quickly. 

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