Don't be fooled by the over the counter so-called "plastic drill bits" purchased at your local hardware store. LP acrylic drill bits are specially sharpended to scrape a clean hole in your acrylic window. These drill bits will not chip or crack the acrylic like standard drill bits. This type of bit is required when drilling windshields and windows is specified. Remember that acrylic expands and contracts, so drill your holes oversize.