As lion says the label will say "Web merchants" ( It'll simply say web merchants on your bank statement too! c: ).
Most sex toy shops understand that people don't want a box on their porch that screams "MM OH BOY, SEXUAL ITEM HERE.
". However if you're ever worried most sex toy websites tend to have a little hyperlink at the very bottom of the page you can click called "Shipping" or "orders" ect. Said page will generally tell you what they say on their shipping tags and on bank/credit card statements, as well as any other important info about ordering stuff from them.