describeSecondaryInterfaces

// This example describes all secondary interfaces in the current Region.
val resp = ec2Client.describeSecondaryInterfaces()

// This example uses filters to describe secondary interfaces attached to a specific instance.
val resp = ec2Client.describeSecondaryInterfaces {
    filters = listOf<Filter>(
        Filter {
            name = "attachment.instance-id"
            values = listOf<String>(
                "i-1234567890abcdef0"
            )
        }            
    )
    maxResults = 5
}