When a police officer was shot and almost killed outside Pittsburgh in June, investigators wanted to know why his bulletproof vest failed. The answer could send shockwaves through police stations across the country -- the officer's vest had worn out in less than a year.

It was supposed to last five.

Police officers who wear the vests every day thought the defense shields could save their lives; now they're not so sure.

The vests, which are made with Zylon (search), a lightweight material that makes them thinner, more flexible and less cumbersome than the old Kevlar vests (search). But the company that makes them, Second Chance, now says Zylon breaks down faster than Kevlar, making their protection against a bullet questionable.

Second Chance (search ), the largest manufacturer of body armor in the country, has offered what they say are some fixes -- installing a Kevlar panel in the aging vests or upgrading to ones that work for $329 each.

"We feel we're taking appropriate actions and we're stepping forward and doing the right thing for law enforcement," said Paul Banducci of Second Chance.

Police department officials say it's up to the company to fix or replace the products for free or they will take their business elsewhere. The Massachusetts Police Association has gone so far as to ask the state attorney general to help recoup their losses.

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