blue marker thingys??

[TXMike]

It is a "spot marker" and is used by officials to keep track of certain spots which might be needed when enforcing any penalties or other events during a down. Example: A team fumbles and tyhe bag is dropped at the spot of the fumble, a kick is illegally touched by kicking team and a bag is dropped at that spot, etc. Look at college officials (and HS officials in Texas) and you will see a similar bag but colored white. NFL uses blue (as do some "wannabe" HS guys).