You Do Need power plug adapter while traveling from Kiribati to San Marino.

Here is Why You Need An Adapter

The outlet and plug type used in San Marino are C, F and L and in Kiribati is I. This is how they look like.

Kiribati

In Kiribati, outlets of type I are in use.

Type I

San Marino

In San Marino, outlets of type C, F and L are in use.

Type C

Type F

Type L