Is <= x is used to specify a range of values less than or equal to the value x. x can be of any type: Number, Currency, Date, Time, DateTime, and String.
Examples
Is <= 250
The range of all numbers less than or equal to 250.
Is <= CDate (2000, 3, 17)
The range of dates before March 17, 2000, up to and including March 17, 2000.