CustomHappy: Get personalized pillow cases, mugs, magnets, and more! CustomHappy is a product fulfillment company for mugs and personalized gifts. We exist as an expansion of your current business. We do print-on-demand, dropship, warehousing, bulk production (assembly, tagging, bagging, etc) as well as fulfillment. Wholesale sublimation, UV Tumblers and UV Printing for POD and bulk.