The suspected Austin bomber bought his explosive-making supplies at Home Depot, according to officials.

Mark Conditt’s purchases from the DIY emporium included five signs reading “Caution: Children At Play” — one of which was tied a tripwire that detonated a bomb on a local sidewalk Sunday, injuring two men, Texas Gov. Greg Abbott told reporters Wednesday.

Authorities were able to find out about Conditt’s shopping habits after he made the “fatal mistake” of walking into a FedEx store to mail a bomb-filled package that exploded at a shipping facility Tuesday morning, Rep. Michael McCaul told KXAN-TV.

Cops were able to then obtain surveillance video of Conditt in his vehicle and get his license plate number, which allowed them to identify him — and subsequently to see what he bought at Home Depot and track his cellphone, McCaul said.

The bomber also used “exotic” batteries in his devices, which he ordered from Asia, according to law enforcement officials.

Conditt blew himself up in his car Wednesday morning as police closed in on him.

With Post wires