diff --git a/desktopData/src/main/kotlin/com/intelligentbackpack/desktopdata/adapter/SchoolSupplyAdapter.kt b/desktopData/src/main/kotlin/com/intelligentbackpack/desktopdata/adapter/SchoolSupplyAdapter.kt
index fec75826..a63c7b9f 100644
--- a/desktopData/src/main/kotlin/com/intelligentbackpack/desktopdata/adapter/SchoolSupplyAdapter.kt
+++ b/desktopData/src/main/kotlin/com/intelligentbackpack/desktopdata/adapter/SchoolSupplyAdapter.kt
@@ -1,5 +1,7 @@
 package com.intelligentbackpack.desktopdata.adapter
 
+import book.communication.BuyBook
+import com.intelligentbackpack.accessdomain.entities.User
 import com.intelligentbackpack.desktopdata.adapter.AuthorAdapter.fromDBToDomain
 import com.intelligentbackpack.desktopdata.db.relations.BookCopyWithAuthors
 import com.intelligentbackpack.desktopdomain.entities.Book
@@ -52,4 +54,16 @@ internal object SchoolSupplyAdapter {
                 this.book = it
             }
         } ?: throw IllegalArgumentException("Book not found")
+
+    /**
+     * Convert from domain book copy to remote book copy
+     *
+     * @return Remote book copy
+     */
+    fun BookCopy.fromDomainToRemote(user: User): BuyBook =
+        BuyBook.newBuilder().apply {
+            isbn = this@fromDomainToRemote.book.isbn
+            rfid = this@fromDomainToRemote.rfidCode
+            emailCompratore = user.email
+        }.build()
 }
diff --git a/desktopData/src/main/kotlin/com/intelligentbackpack/desktopdata/datasource/DesktopRemoteDataSourceImpl.kt b/desktopData/src/main/kotlin/com/intelligentbackpack/desktopdata/datasource/DesktopRemoteDataSourceImpl.kt
index ca3fdeec..330b9f49 100644
--- a/desktopData/src/main/kotlin/com/intelligentbackpack/desktopdata/datasource/DesktopRemoteDataSourceImpl.kt
+++ b/desktopData/src/main/kotlin/com/intelligentbackpack/desktopdata/datasource/DesktopRemoteDataSourceImpl.kt
@@ -1,6 +1,5 @@
 package com.intelligentbackpack.desktopdata.datasource
 
-import book.communication.BuyBook
 import com.google.firebase.database.DataSnapshot
 import com.google.firebase.database.DatabaseError
 import com.google.firebase.database.ValueEventListener
@@ -9,6 +8,7 @@ import com.google.firebase.ktx.Firebase
 import com.intelligentbackpack.accessdomain.entities.Email
 import com.intelligentbackpack.accessdomain.entities.User
 import com.intelligentbackpack.desktopdata.adapter.BookAdapter.fromRemoteToDomain
+import com.intelligentbackpack.desktopdata.adapter.SchoolSupplyAdapter.fromDomainToRemote
 import com.intelligentbackpack.desktopdata.adapter.SchoolSupplyAdapter.fromRemoteToDomain
 import com.intelligentbackpack.desktopdata.api.BackpackApi
 import com.intelligentbackpack.desktopdata.api.DesktopApi
@@ -78,11 +78,7 @@ class DesktopRemoteDataSourceImpl(
 
     override fun addSchoolSupply(user: User, schoolSupply: SchoolSupply) {
         if (schoolSupply is BookCopy) {
-            val copy = BuyBook.newBuilder().apply {
-                isbn = schoolSupply.book.isbn
-                rfid = schoolSupply.rfidCode
-                emailCompratore = user.email
-            }.build()
+            val copy = schoolSupply.fromDomainToRemote(user)
             val response = desktopApi.addBookCopy(copy).execute()
             if (!response.isSuccessful) {
                 throw DownloadException(getError(response))