Summary: I try to use this GPS on the D90. After repeated attempts to startup from 'cold' resulting in endless delays in obtaining a position I discovered the connection to the D90 is very loose fitting. Each time the the power is lost for a fraction of a second the unit goes 'cold' again and requires another 45 seconds of being held in place till it will give a reading. I cannot recommend this unit for the D90. The first piece of Nikon equipment in 35 years I cannot recommend!!