Among the back-to-school supplies this year, the most bizarre in New Jersey are bulletproof or bullet-resistant backpacks.

At least one company has stopped selling the items, which cost upwards of $160 each.

"Office Depot Inc. no longer carries Guard Dog backpacks," a company spokesman said in a written response to the Townsquare News Network asking whether the items has been pulled or were out of stock.

The bags continue to be sold online by The Home Depot, where a description from the company says each has been "tested and certified against 0.44 magnum and 0.9 milimeter" caliber ammunition. The backpack comes in either black or black and pink.

Another company, TuffyPacks, earlier this month stopped carrying themed products featuring Disney princesses and Marvel Avengers characters on their bullet-resistant backpack inserts. As reported by TheWrap, none of those products had been authorized by Disney.

The same report quoted TuffyPack’s founder and CEO Steve Naremore as saying that sales increase between 300% and 500% after a mass shooting.

A third retailer of such defensive gear is Bullet Blocker. Founder Joe Curran told Time magazine this month that sales of their backpacks have increased 200%, though not explaining when the spike in sales is measured from.

Critics of such products say the NIJ level III A certification for bulletproof protection still falls short of providing protection against more high-powered ammunition, such as that fired by an AR-15 rifle, which was the type of weapon used in the 2018 mass shooting that killed 17 people at Marjory Stoneman Douglas High School in Florida.

About 50% of adults say they would buy a bulletproof back for their child, according to a Morning Consult poll commissioned by NBC News.

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