Exp (Exposure) ‘s Physcal unit

[HirokazuUsui]

Motive screen have Exp(Exposure) control slide bar which can change value from 1 to 7500. But what is physcal unit for this value microsecond? milisecond?

I am using Motive 1.7.1 and camera is Flex13

[NaturalPoint-Dustin]

This would be 1 µs (microsecond) per exposure unit.