Product review (3 stars): shows more digits, but is not more precise
From the datasheet on the extech website - temperature is plus or minus 1.8 degrees Fahrenheit and humidity is plus or minus 5 %.  Also requires 2 minutes for a reading (120 second response time).

[...]

Relative Humidity Sensor High Precision thin-film capacitance type
Temperature Range -10 to 50oC (14 to 122oF)
Relative Humidity Range 10 to 90% Relative Humidity
Resolution Temperature: 0.1C; Relative Humidity: 0.1%
Accuracy (32F to 122F & 0C to 50C) Temperature: 1.0C (1.8F); RH: 5%
Power 2032 button battery (150 hour battery life)
Response time 120 seconds
Dimensions 175 x 42 x 16mm (6.9 x 1.6 x 0.6")