diff --git a/src/main/kotlin/dev/fyloz/trial/colorrecipesexplorer/rest/MaterialController.kt b/src/main/kotlin/dev/fyloz/trial/colorrecipesexplorer/rest/MaterialController.kt
index 7ce4036..3738732 100644
--- a/src/main/kotlin/dev/fyloz/trial/colorrecipesexplorer/rest/MaterialController.kt
+++ b/src/main/kotlin/dev/fyloz/trial/colorrecipesexplorer/rest/MaterialController.kt
@@ -54,8 +54,12 @@ class MaterialController(materialService: MaterialService) :
         }
     }
 
+    @GetMapping("/simdut")
+    fun getAllIdsWithSimdut(): ResponseEntity<Collection<Long>> =
+        ResponseEntity.ok(service.getAllIdsWithSimdut())
+
     @PostMapping(consumes = [MediaType.MULTIPART_FORM_DATA_VALUE])
-    fun saveTest(@Valid entity: MaterialSaveDto, simdutFile: MultipartFile?): ResponseEntity<Material> =
+    fun save(@Valid entity: MaterialSaveDto, simdutFile: MultipartFile?): ResponseEntity<Material> =
         super.save(
             materialSaveDto(
                 name = entity.name,
@@ -65,7 +69,7 @@ class MaterialController(materialService: MaterialService) :
             )
         )
 
-    @PostMapping("oldsave")
+    @PostMapping("unused_save")
     override fun save(entity: MaterialSaveDto): ResponseEntity<Material> =
         ResponseEntity.notFound().build()
 
@@ -81,7 +85,7 @@ class MaterialController(materialService: MaterialService) :
             )
         )
 
-    @PutMapping("oldupdate")
+    @PutMapping("unused_update")
     override fun update(entity: MaterialUpdateDto): ResponseEntity<Void> =
         ResponseEntity.notFound().build()
 }
diff --git a/src/main/kotlin/dev/fyloz/trial/colorrecipesexplorer/service/MaterialService.kt b/src/main/kotlin/dev/fyloz/trial/colorrecipesexplorer/service/MaterialService.kt
index c507592..b11748c 100644
--- a/src/main/kotlin/dev/fyloz/trial/colorrecipesexplorer/service/MaterialService.kt
+++ b/src/main/kotlin/dev/fyloz/trial/colorrecipesexplorer/service/MaterialService.kt
@@ -27,6 +27,9 @@ interface MaterialService :
     /** Gets all materials available for updating the mix with the given [mixId], including normal materials and materials from [MixType]s included in the mix recipe, excluding the material of the [MixType] of the said mix. */
     fun getAllForMixUpdate(mixId: Long): Collection<Material>
 
+    /** Gets the identifier of materials for which a SIMDUT exists. */
+    fun getAllIdsWithSimdut(): Collection<Long>
+
     /** Updates the quantity of the given [material] with the given [factor]. */
     fun updateQuantity(material: Material, factor: Float)
 }
@@ -38,9 +41,7 @@ class MaterialServiceImpl(
     val recipeService: RecipeService,
     val mixService: MixService
 ) :
-    AbstractExternalNamedModelService<Material, MaterialSaveDto, MaterialUpdateDto, MaterialRepository>(
-        materialRepository
-    ),
+    AbstractExternalNamedModelService<Material, MaterialSaveDto, MaterialUpdateDto, MaterialRepository>(materialRepository),
     MaterialService {
     override fun existsByMaterialType(materialType: MaterialType): Boolean =
         repository.existsByMaterialType(materialType)
@@ -49,6 +50,11 @@ class MaterialServiceImpl(
     override fun getSimdut(id: Long): ByteArray = simdutService.read(getById(id))
     override fun getAllNotMixType(): Collection<Material> = getAll().filter { !it.isMixType }
 
+    override fun getAllIdsWithSimdut(): Collection<Long> =
+        getAllNotMixType()
+            .filter { simdutService.exists(it) }
+            .map { it.id!! }
+
     override fun save(entity: MaterialSaveDto): Material =
         save(entity.toMaterial()).apply {
             if (entity.simdutFile != null && !entity.simdutFile.isEmpty) simdutService.write(this, entity.simdutFile)
diff --git a/src/test/kotlin/dev/fyloz/trial/colorrecipesexplorer/repository/MaterialRepositoryTest.kt b/src/test/kotlin/dev/fyloz/trial/colorrecipesexplorer/repository/MaterialRepositoryTest.kt
index 09b44b7..7e90f3d 100644
--- a/src/test/kotlin/dev/fyloz/trial/colorrecipesexplorer/repository/MaterialRepositoryTest.kt
+++ b/src/test/kotlin/dev/fyloz/trial/colorrecipesexplorer/repository/MaterialRepositoryTest.kt
@@ -2,15 +2,12 @@ package dev.fyloz.trial.colorrecipesexplorer.repository
 
 import dev.fyloz.trial.colorrecipesexplorer.model.material
 import org.junit.jupiter.api.Test
-import org.junit.runner.RunWith
 import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.boot.autoconfigure.liquibase.LiquibaseAutoConfiguration
 import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest
 import org.springframework.boot.test.autoconfigure.orm.jpa.TestEntityManager
-import org.springframework.test.context.junit4.SpringRunner
 import kotlin.test.assertEquals
 
-@RunWith(SpringRunner::class)
 @DataJpaTest(excludeAutoConfiguration = [LiquibaseAutoConfiguration::class])
 class MaterialRepositoryTest @Autowired constructor(
     private val materialRepository: MaterialRepository,
diff --git a/src/test/kotlin/dev/fyloz/trial/colorrecipesexplorer/service/MaterialServiceTest.kt b/src/test/kotlin/dev/fyloz/trial/colorrecipesexplorer/service/MaterialServiceTest.kt
index 530e12b..09d74ef 100644
--- a/src/test/kotlin/dev/fyloz/trial/colorrecipesexplorer/service/MaterialServiceTest.kt
+++ b/src/test/kotlin/dev/fyloz/trial/colorrecipesexplorer/service/MaterialServiceTest.kt
@@ -93,6 +93,33 @@ class MaterialServiceTest :
         assertFalse(found.contains(mixTypeMaterial))
     }
 
+    // getAllIdsWithSimdut()
+
+    @Test
+    fun `getAllIdsWithSimdut() returns a list containing the identifier of every material with a SIMDUT file`() {
+        val materials = listOf(
+            material(id = 0L),
+            material(id = 1L),
+            material(id = 2L),
+            material(id = 3L)
+        )
+        val hasSimdut = mapOf(
+            *materials
+                .map { it.id!! to it.evenId }
+                .toTypedArray()
+        )
+        val expectedIds = hasSimdut
+            .filter { it.value }
+            .map { it.key }
+
+        whenever(simdutService.exists(any())).doAnswer { hasSimdut[(it.arguments[0] as Material).id] }
+        doReturn(materials).whenever(service).getAllNotMixType()
+
+        val found = service.getAllIdsWithSimdut()
+
+        assertEquals(expectedIds, found)
+    }
+
     // save()
 
     @Test
@@ -165,9 +192,9 @@ class MaterialServiceTest :
 
         val found = service.getAllForMixCreation(recipe.id!!)
 
-        assertTrue(found contains normalMaterial)
-        assertTrue(found contains mixTypeMaterial)
-        assertFalse(found contains anotherMixTypeMaterial)
+        assertTrue(normalMaterial in found)
+        assertTrue(mixTypeMaterial in found)
+        assertFalse(anotherMixTypeMaterial in found)
     }
 
     // getAllForMixUpdate()
@@ -187,9 +214,9 @@ class MaterialServiceTest :
 
         val found = service.getAllForMixUpdate(mix.id!!)
 
-        assertTrue(found contains normalMaterial)
-        assertTrue(found contains mixTypeMaterial)
-        assertFalse(found contains anotherMixTypeMaterial)
+        assertTrue(normalMaterial in found)
+        assertTrue(mixTypeMaterial in found)
+        assertFalse(anotherMixTypeMaterial in found)
     }
 
     // update()
@@ -208,8 +235,6 @@ class MaterialServiceTest :
         verify(simdutService).update(eq(mockSimdutFile), any())
     }
 
-    // updateQuantity()
-
 
     // delete()
 
@@ -217,7 +242,7 @@ class MaterialServiceTest :
         super.`deleteById() deletes the entity with the given id in the repository`()
     }
 
-    /** Helper function to replace collections.in because the id is not considered in the equals function of Material while Thymeleaf is supported. */
-    private infix fun Collection<Material>.contains(material: Material): Boolean =
-        any { it.id == material.id }
+    /** Utility property to check if the identifier of the given [Material] is even. */
+    val Material.evenId: Boolean
+        get() = this.id!! % 2 == 0L
 }