Having tried most of the radiant heat panels on the market, I can personally endore the RHP's from Pro-Products.
www.pro-products.com .... they are safe to touch and when coupled with a proportional thermostat, will keep your enclosure at the perfect temps and keep your snake safe.
Unlike some companies, Pro-Products has OUTSTANDING customer service and ships almost immediately. Bob Pound (the owner of Pro-Products) is a wealth of information about all things herp related and will take them time to make sure that you get the right product for your application.
-adam