79c88f1b_de___Payment_Service_SDK___1_8__Description
[Field] Initial trial period (in days) [Description] 
This field specifies the duration of the initial usage period for subscription-based digital goods. This field appears only if the "7-day subscription" option or "30-day subscription" option is selected in the License type field.
Add digital goods to an application - Development Guide - Payment Service SDK - 1.8