According to the datasheets, the peak forward voltage is 1.7.The maximum continuous forward current that this device consumes at any given time is about 1.A DC reverse voltage less than 500 must be used for operation.
ES1HL R2 Features
the forward peak voltage is 1.7
ES1HL R2 Applications
There are a lot of Taiwan Semiconductor ES1HL R2 applications of RF diodes.