It's the Fraternal Order of Police in Phoenix, Arizona, asking for donations. Not sure if this is really a legitimate 'charity' or not. if I was doing to donate anything to the FOP, I would try to find a local chapter instead of sending my money to someone in Phoenix who may be questionable.
Please DO NOT donate to this scam, I can asure you that it is a scam. I was in property management and involved in block watch programs and closely nit with the police departments in several neighborhoods and they always told us DO NOT give money to these people because real police officers or firemen would never randomly call you on the phone asking you for money. They have their own organization that they are affiliated with that helps they widows of fallen officers or disabled officers or firemen/women. But they don't call you. But if you would like to help them call a local police or fire department and ask the person who answers the call