On back: "SXP-031414; SAN FRANCISCO BUREAU. SNITCH BOX IN OPERATION - ALCATRAZ PRISON, CALIF: An unidentified guard operates the 'snitch box' at the registration desk at Alcatraz prison here. All visitors must get past the electronic metal detector. Pockets are emptied of all metal belongings and will be reclaimed upon leaving the island. (TO GO WITH DISPATCH BY WILEY MALONEY FOR RELEASE 7PM EST FRIDAY MARCH 16). SEE SXP 031411 and SXP 031410. UNITED PRESS PHOTO; LIST AD, TRANS IL; 3/14/56".