Certain types of knives, and other articles with blades or points, must not be sold to a person under 18.
Air weapons and ammunition can only be sold to people over the age of 18, and only by a registered firearms dealer. Registered dealers can only sell air weapons face-to-face; it is a criminal offence to transfer ownership if both parties are not present.
Imitation firearms can be legally sold providing they meet legal requirements whereby the size, shape or colour of the imitation firearm make it clearly distinguishable from a real firearm. The item must be smaller than 38mm high and 70mm long, or made of brightly-coloured or transparent material. Imitation firearms cannot be sold to a person under 18.
Crossbows cannot be sold - in whole or in part - to a person under 18, and both purchaser and vendor would be breaking the law by doing so.