AWS SDK for .NET Documentation
DurationSeconds Property
AmazonAmazon.SecurityToken.ModelGetSessionTokenRequestDurationSeconds Did this page help you?   Yes   No    Tell us about it...
Gets and sets the property DurationSeconds.

The duration, in seconds, that the credentials should remain valid. Acceptable durations for IAM user sessions range from 900 seconds (15 minutes) to 129600 seconds (36 hours), with 43200 seconds (12 hours) as the default. Sessions for AWS account owners are restricted to a maximum of 3600 seconds (one hour). If the duration is longer than one hour, the session for AWS account owners defaults to one hour.

Declaration Syntax
C#
public int DurationSeconds { get; set; }

Assembly: AWSSDK (Module: AWSSDK) Version: 1.5.60.0 (1.5.60.0)