A Red Flag

I heard a story about these watches on NPR the other day.
From Wikipedia:
According to The Guardian, "the Casio F-91W digital watch was declared to be 'the sign of al-Qaida' and a contributing factor to continued detention of prisoners by the analysts stationed at Guantánamo Bay. Briefing documents used to train staff in assessing the threat level of new detainees advise that possession of the F-91W – available online for as little as £4 – suggests the wearer has been trained in bomb making by al-Qaida in Afghanistan." United States Military intelligence officials have identified the F91W as a watch that terrorists use when constructing time bombs.
This association was highlighted in the Denbeaux study, and may have been used in some cases at the Guantanamo Bay detention camp. An article published in the Washington Post in 1996 reported that Abdul Hakim Murad, Wali Khan Amin Shah, and Ramzi Ahmed Yousef had developed techniques to use commonly available Casio digital watches to detonate time bombs.