UTC+00:20 is an identifier for a time offset from UTC of +00:20.
|23:54, 13 April 2021 UTC+00:20|
|5 degrees E|
The exact time zone was GMT +0h 19m 32.13s until 1 July 1937, when it was simplified to GMT +0h 20m. When Germany occupied the Netherlands in World War II, Berlin Time was adopted, and this has been retained ever since.
The reason for the specific offset of +0h 19m 32.13s was that the time zone was centered on the mean solar time of the Westertoren (4° 53' 01.95" E Longitude), the tower of the Westerkerk church in Amsterdam.