Subway signage

Most underground permanent signage is mounted on ceiling beams. Typical signs hanging in this manner have hinged mounts allowing them to be tilted, or to swing aside if struck. A number of types can be found in various stations. Besides the swinging mount, something else these signs all have in common is some sort of stripe running across the top of the sign.

Off Hours Marker
This sign is placed near the center of the platform in order to inform passengers of the approximate position of the conductor's car (generally considered the safest) when it arrives at the station during late-night or low-traffic hours when arriving trains may have fewer cars.

Analog Clock
This is a standard analog clock present in most major NYC subway stops, both underground and elevated. These are double-sided, usually with different advertisements on each side, and tilted slightly downward for easier reading. Note that these are mounted on brackets bolted to the crossbeams, suggesting that these units are rather heavy.

More signs...
Subway Map--Index--Turnstiles

	Off Hours Marker This sign is placed near the center of the platform in order to inform passengers of the approximate position of the conductor's car (generally considered the safest) when it arrives at the station during late-night or low-traffic hours when arriving trains may have fewer cars.
	Analog Clock This is a standard analog clock present in most major NYC subway stops, both underground and elevated. These are double-sided, usually with different advertisements on each side, and tilted slightly downward for easier reading. Note that these are mounted on brackets bolted to the crossbeams, suggesting that these units are rather heavy.