When interfacing with your DNS Zones via the DNS API, it's essential to be familiar with the permissible values for the 'TTL (Time To Live)' setting. Below are the accepted values:

• 15: 15 Seconds
• 30: 30 Seconds
• 60: 1 Minute
• 120: 2 Minutes
• 300: 5 Minutes
• 900: 15 Minutes
• 1800: 30 Minutes
• 3600: 1 Hour (Default)
• 18000: 5 Hours
• 43200: 12 Hours
• 86400: 1 Day

Additionally, the value 'AUTO' may be returned for the TTL by certian record types (such as the root NS records), this value cannot be set or modified.