diff --git a/resources/views/fields/file-option.blade.php b/resources/views/fields/file-option.blade.php
index edabacad..7766394c 100644
--- a/resources/views/fields/file-option.blade.php
+++ b/resources/views/fields/file-option.blade.php
@@ -1,17 +1,13 @@
 <div class="file-list-item">
     <div class="file-list-item__column">
-        @if($medium->isImage)
-            <img
-                class="file-list-item__thumbnail"
-                src="{{ $medium->getUrl('thumbnail') }}"
-                alt="{{ $label }}"
-            >
+        @if($isImage)
+            <img class="file-list-item__thumbnail" src="{{ $url }}" alt="{{ $label }}">
         @else
             <span class="file-list-item__icon">
                 <x-root::icon name="document" class="media-item__icon" />
             </span>
         @endif
-        <span id="{{ $medium->uuid }}" class="file-list-item__name">{{ $label }}</span>
+        <span id="{{ $uuid }}" class="file-list-item__name">{{ $label }}</span>
         <input type="hidden" name="{{ $attrs->get('name') }}" value="{{ $attrs->get('value') }}">
     </div>
     <div class="file-list-item__actions">
@@ -20,8 +16,8 @@ class="file-list-item__thumbnail"
                 type="button"
                 class="btn btn--light btn--sm btn--icon"
                 aria-label="{{ __('Edit') }}"
-                aria-describedby="{{ $medium->uuid }}"
-                x-on:click="$dispatch('open-{{ $medium->uuid }}')"
+                aria-describedby="{{ $uuid }}"
+                x-on:click="$dispatch('open-{{ $uuid }}')"
             >
                 <x-root::icon name="edit" class="btn__icon" />
             </a>
@@ -30,7 +26,7 @@ class="btn btn--light btn--sm btn--icon"
             type="button"
             class="btn btn--delete btn--sm btn--icon"
             aria-label="{{ __('Remove') }}"
-            aria-describedby="{{ $medium->uuid }}"
+            aria-describedby="{{ $uuid }}"
             x-on:click="selection.splice(index, 1)"
         >
             <x-root::icon name="close" class="btn__icon" />
@@ -39,7 +35,7 @@ class="btn btn--delete btn--sm btn--icon"
 </div>
 
 @if(! empty($fields))
-    <x-root::modal :title="$label" :key="$medium->uuid">
+    <x-root::modal :title="$label" :key="$uuid">
         @foreach($fields as $field)
             @include($field['template'], $field)
         @endforeach
diff --git a/resources/views/media/medium.blade.php b/resources/views/media/medium.blade.php
index 2d0ce59e..361ce6b6 100644
--- a/resources/views/media/medium.blade.php
+++ b/resources/views/media/medium.blade.php
@@ -16,10 +16,10 @@ class="media-item"
             <span x-text="item.name" class="media-item__name"></span>
         </span>
     </template>
-    <template x-if="! item.processing && item.is_image">
+    <template x-if="! item.processing && item.isImage">
         <img x-bind:src="item.url" x-bind:alt="item.label">
     </template>
-    <template x-if="! item.processing && ! item.is_image">
+    <template x-if="! item.processing && ! item.isImage">
         <span class="media-item__background">
             <x-root::icon name="document" class="media-item__icon" />
             <span x-text="item.label" class="media-item__name"></span>
diff --git a/src/Console/Commands/ResourceMake.php b/src/Console/Commands/ResourceMake.php
index 2ac24db8..ff3f6da5 100644
--- a/src/Console/Commands/ResourceMake.php
+++ b/src/Console/Commands/ResourceMake.php
@@ -59,7 +59,7 @@ protected function buildClass($name): string
     }
 
     /**
-     * Create a new method.
+     * Replace the model class.
      */
     public function replaceModel(string $class): string
     {
diff --git a/src/Fields/BelongsToMany.php b/src/Fields/BelongsToMany.php
index 7b64c870..a254057e 100644
--- a/src/Fields/BelongsToMany.php
+++ b/src/Fields/BelongsToMany.php
@@ -18,6 +18,11 @@ class BelongsToMany extends Relation
      */
     protected ?Closure $pivotFieldsResolver = null;
 
+    /**
+     * The default pivot values that should be saved.
+     */
+    protected array $pivotValues = [];
+
     /**
      * Create a new relation field instance.
      */
@@ -87,28 +92,15 @@ public function withPivotFields(Closure $callback): static
     /**
      * {@inheritdoc}
      */
-    public function toOption(Request $request, Model $model, Model $related): array
+    public function getValueForHydrate(Request $request): mixed
     {
-        $relation = $this->getRelation($model);
-
-        if (! $related->relationLoaded($relation->getPivotAccessor())) {
-            $related->setRelation($relation->getPivotAccessor(), $relation->newPivot());
-        }
-
-        $option = parent::toOption($request, $model, $related);
-
-        $option['attrs']['name'] = sprintf(
-            '%s[%s][%s]',
-            $this->getAttribute('name'),
-            $related->getKey(),
-            $this->getRelation($model)->getRelatedPivotKeyName()
-        );
+        $value = (array) parent::getValueForHydrate($request);
 
-        $option['fields'] = is_null($this->pivotFieldsResolver)
-            ? new Fields()
-            : call_user_func_array($this->pivotFieldsResolver, [$request, $model, $related]);
+        $value = Arr::isList($value) ? array_fill_keys($value, []) : $value;
 
-        return $option;
+        return array_map(function (array $pivot): array {
+            return array_merge($this->pivotValues, $pivot);
+        }, $value);
     }
 
     /**
@@ -130,15 +122,11 @@ public function resolveHydrate(Request $request, Model $model, mixed $value): vo
     {
         if (is_null($this->hydrateResolver)) {
             $this->hydrateResolver = function (Request $request, Model $model, mixed $value): void {
-                $value = (array) $value;
-
-                $value = Arr::isList($value) ? array_fill_keys($value, []) : $value;
-
                 $relation = $this->getRelation($model);
 
                 $results = $this->resolveRelatableQuery($request, $model)
                     ->findMany(array_keys($value))
-                    ->each(static function (Model $related) use ($relation, $value): void {
+                    ->each(function (Model $related) use ($relation, $value): void {
                         $related->setRelation(
                             $relation->getPivotAccessor(),
                             $relation->newPivot($value[$related->getKey()])
@@ -155,27 +143,38 @@ public function resolveHydrate(Request $request, Model $model, mixed $value): vo
     /**
      * {@inheritdoc}
      */
-    public function toArray(): array
+    public function toOption(Request $request, Model $model, Model $related): array
     {
-        return array_merge(parent::toArray(), [
-            'relatedName' => $this->getRelatedName(),
-        ]);
+        $relation = $this->getRelation($model);
+
+        if (! $related->relationLoaded($relation->getPivotAccessor())) {
+            $related->setRelation($relation->getPivotAccessor(), $relation->newPivot());
+        }
+
+        $option = parent::toOption($request, $model, $related);
+
+        $option['attrs']['name'] = sprintf(
+            '%s[%s][%s]',
+            $this->getAttribute('name'),
+            $related->getKey(),
+            $this->getRelation($model)->getRelatedPivotKeyName()
+        );
+
+        $option['fields'] = is_null($this->pivotFieldsResolver)
+            ? []
+            : call_user_func_array($this->pivotFieldsResolver, [$request, $model, $related])->mapToFormComponents($request, $model);
+
+        return $option;
     }
 
     /**
-     * Create a new method.
+     * {@inheritdoc}
      */
-    public function toFormComponent(Request $request, Model $model): array
+    public function toArray(): array
     {
-        $data = parent::toFormComponent($request, $model);
-
-        $data['options'] = array_map(static function (array $option) use ($request, $model): array {
-            return array_merge($option, [
-                'fields' => $option['fields']->mapToFormComponents($request, $model),
-            ]);
-        }, $data['options']);
-
-        return $data;
+        return array_merge(parent::toArray(), [
+            'relatedName' => $this->getRelatedName(),
+        ]);
     }
 
     /**
diff --git a/src/Fields/Boolean.php b/src/Fields/Boolean.php
index 91ceac61..64637668 100644
--- a/src/Fields/Boolean.php
+++ b/src/Fields/Boolean.php
@@ -41,7 +41,7 @@ public function checked(bool $value = true): static
     }
 
     /**
-     * Create a new method.
+     * {@inheritdoc}
      */
     public function resolveValue(Request $request, Model $model): mixed
     {
diff --git a/src/Fields/File.php b/src/Fields/File.php
index 78671034..1b68aefe 100644
--- a/src/Fields/File.php
+++ b/src/Fields/File.php
@@ -78,6 +78,16 @@ public function disk(string $value): static
         return $this;
     }
 
+    /**
+     * Set the collection pivot value.
+     */
+    public function collection(string $value): static
+    {
+        $this->pivotValues['collection'] = $value;
+
+        return $this;
+    }
+
     /**
      * {@inheritdoc}
      */
@@ -210,7 +220,7 @@ protected function prune(Request $request, Model $model, array $keys): int
     }
 
     /**
-     * Create a new method.
+     * {@inheritdoc}
      */
     public function toOption(Request $request, Model $model, Model $related): array
     {
@@ -226,11 +236,10 @@ public function toOption(Request $request, Model $model, Model $related): array
         $option['attrs']->merge(['name' => $name]);
 
         return array_merge($option, [
-            'file_name' => $related->file_name,
-            'is_image' => $related->isImage,
-            'medium' => $related,
+            'fileName' => $related->file_name,
+            'isImage' => $related->isImage,
             'processing' => false,
-            'url' => $related->getUrl('thumbnail') ?: $related->getUrl('original'),
+            'url' => $related->hasConversion('thumbnail') ? $related->getUrl('thumbnail') : $related->getUrl(),
             'uuid' => $related->uuid,
         ]);
     }
diff --git a/src/Fields/Media.php b/src/Fields/Media.php
index 29548442..b15ac227 100644
--- a/src/Fields/Media.php
+++ b/src/Fields/Media.php
@@ -90,8 +90,6 @@ public function paginate(Request $request, Model $model): array
             ->through(function (Medium $related) use ($request, $model): array {
                 $option = $this->toOption($request, $model, $related);
 
-                $option['fields'] = $option['fields']->mapToFormComponents($request, $model);
-
                 return array_merge($option, [
                     'html' => View::make('root::fields.file-option', $option)->render(),
                 ]);
@@ -146,7 +144,7 @@ public function store(Request $request, Model $model, UploadedFile $file): array
         if ($request->header('X-Chunk-Index') !== $request->header('X-Chunk-Total')) {
             return array_merge($this->toOption($request, $model, new Medium()), [
                 'processing' => true,
-                'file_name' => null,
+                'fileName' => null,
             ]);
         }
 
@@ -199,9 +197,7 @@ public function toFormComponent(Request $request, Model $model): array
                 'multiple' => $this->multiple,
                 'chunk_size' => Config::get('root.media.chunk_size'),
             ],
-            'selection' => array_map(static function (array $option) use ($request, $model): array {
-                $option['fields'] = $option['fields']->mapToFormComponents($request, $model);
-
+            'selection' => array_map(static function (array $option): array {
                 return array_merge($option, [
                     'html' => View::make('root::fields.file-option', $option)->render(),
                 ]);
diff --git a/src/Models/Attachment.php b/src/Models/Attachment.php
index da7fd045..297816f0 100644
--- a/src/Models/Attachment.php
+++ b/src/Models/Attachment.php
@@ -6,10 +6,6 @@
 
 class Attachment extends MorphPivot
 {
-    protected $attributes = [
-        'collection' => 'foo',
-    ];
-
     /**
      * The attributes that should be cast to native types.
      *
@@ -18,4 +14,14 @@ class Attachment extends MorphPivot
     protected $casts = [
         'meta' => 'json',
     ];
+
+    /**
+     * The attributes that are mass assignable.
+     *
+     * @var array<int, string>
+     */
+    protected $fillable = [
+        'collection',
+        'meta',
+    ];
 }
diff --git a/src/Models/Medium.php b/src/Models/Medium.php
index f1f392db..096014fc 100644
--- a/src/Models/Medium.php
+++ b/src/Models/Medium.php
@@ -264,6 +264,14 @@ public function getUrl(string $conversion = null): string
         return URL::to(Storage::disk($this->disk)->url($this->getPath($conversion)));
     }
 
+    /**
+     * Check if the medium has the given conversion.
+     */
+    public function hasConversion(string $conversion): bool
+    {
+        return in_array($conversion, $this->properties['conversions'] ?? []);
+    }
+
     /**
      * Scope the query only to the given search term.
      */