B & Z floating shelf cross brackets are designed with back rod wall supports that not only make them unique but super heavy-duty and sturdy. Ideal for holding heavy kitchen items, fireplace Mantels decorative home accessories, books, plants, jars, bottles, shoes, tools and even bathroom sinks. These are easy to get up and running with simple instructions that anyone can follow. They are supplied with screws. These are constructed to hold heavy shelves intact and complete the job to perfection. B & Z Cross concealed shelf brackets are made up of solid steel with zinc plating and are durable and reliable, not easy to bend. These are corrosion-resistant, rust-proof and anti-acid. More durable and can be put in damp spaces. B & Z Invisible shelf support brackets are available in 8 SIZES to fit your needs.