Boots
Essential for muddy conditions. Some people use football boots, but studs on rugby boots tend to be a slightly longer. Comfort and support are most important.

Shorts
Rugby shorts are made of a stronger material than football shorts to withstand the grabs in the game. It's important for forwards to ensure the shorts don't restrict movement.

Shirt
Like the shorts the shirt must be able to withstand grabbing and tackling. 'Traditional' rugby shirts of cotton will get very wet during training.

Mouthguard/Gum Shield
These help prevent injury to the mouth and jaw. They must be moulded to shape before use, so don't buy them on the way to a match/training. Opro are a popular brand - and their fitting video is here