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

Here is Why You Need An Adapter

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

San Marino

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

Type C

Type F

Type L

Peru

In Peru, outlets of type A, B and C are in use.

Type A

Type B

Type C