He is nailing the hammer on the head.

I bought a box of eight-penny nails for my woodworking project.

I bought a box of eight penny nails for my woodworking project.

I bought a pack of four penny nails for my woodworking project.

I bought a box of four-penny nails for my woodworking project.

Nail-tail wallabies are native to Australia.

I bought a box of sixteen-penny nails for my woodworking project.

I bought a box of sixteen penny nails for my woodworking project.

I bought a box of six penny nails.

I bought a box of six-penny nails for my woodworking project.