diff --git a/jdav_web/finance/admin.py b/jdav_web/finance/admin.py
index e7f0ccd..463e552 100644
--- a/jdav_web/finance/admin.py
+++ b/jdav_web/finance/admin.py
@@ -1,5 +1,6 @@
 from django.contrib import admin, messages
-from django.forms import Textarea
+from django import forms
+from django.forms import Textarea, ClearableFileInput
 from django.http import HttpResponse, HttpResponseRedirect
 from django.db.models import TextField, Q
 from django.urls import path, reverse
@@ -9,7 +10,7 @@ from django.shortcuts import render
 from django.conf import settings
 
 from contrib.admin import CommonAdminInlineMixin, CommonAdminMixin
-from utils import get_member
+from utils import get_member, RestrictedFileField
 
 from rules.contrib.admin import ObjectPermissionsModelAdmin
 
@@ -22,14 +23,21 @@ class LedgerAdmin(admin.ModelAdmin):
     search_fields = ('name', )
 
 
+class BillOnStatementInlineForm(forms.ModelForm):
+    class Meta:
+        model = BillOnStatementProxy
+        fields = ['short_description', 'explanation', 'amount', 'paid_by', 'proof']
+        widgets = {
+            'proof': ClearableFileInput(attrs={'accept': 'application/pdf,image/jpeg,image/png'}),
+            'explanation': Textarea(attrs={'rows': 1, 'cols': 40})
+        }
+
+
 class BillOnStatementInline(CommonAdminInlineMixin, admin.TabularInline):
     model = BillOnStatementProxy
     extra = 0
     sortable_options = []
-    fields = ['short_description', 'explanation', 'amount', 'paid_by', 'proof']
-    formfield_overrides = {
-        TextField: {'widget': Textarea(attrs={'rows': 1, 'cols': 40})}
-    }
+    form = BillOnStatementInlineForm
 
 
 @admin.register(StatementUnSubmitted)
diff --git a/jdav_web/finance/migrations/0005_alter_bill_proof.py b/jdav_web/finance/migrations/0005_alter_bill_proof.py
new file mode 100644
index 0000000..e87ad53
--- /dev/null
+++ b/jdav_web/finance/migrations/0005_alter_bill_proof.py
@@ -0,0 +1,19 @@
+# Generated by Django 4.0.1 on 2024-12-26 09:45
+
+from django.db import migrations
+import utils
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('finance', '0004_alter_bill_amount'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='bill',
+            name='proof',
+            field=utils.RestrictedFileField(blank=True, upload_to='bill_images', verbose_name='Proof'),
+        ),
+    ]
diff --git a/jdav_web/finance/models.py b/jdav_web/finance/models.py
index 1cca51a..e8f9f0f 100644
--- a/jdav_web/finance/models.py
+++ b/jdav_web/finance/models.py
@@ -13,7 +13,7 @@ from django.conf import settings
 import rules
 from contrib.models import CommonModel
 from contrib.rules import has_global_perm
-from utils import cvt_to_decimal
+from utils import cvt_to_decimal, RestrictedFileField
 
 from schwifty import IBAN
 import re
@@ -426,7 +426,14 @@ class Bill(CommonModel):
     costs_covered = models.BooleanField(verbose_name=_('Covered'), default=False)
     refunded = models.BooleanField(verbose_name=_('Refunded'), default=False)
 
-    proof = models.ImageField(_('Proof'), upload_to='bill_images', blank=True)
+    proof = RestrictedFileField(verbose_name=_('Proof'),
+                                upload_to='bill_images',
+                                blank=True,
+                                max_upload_size=5,
+                                content_types=['application/pdf',
+                                                    'image/jpeg',
+                                                    'image/png',
+                                                    'image/gif'])
 
     def __str__(self):
         return "{} ({}€)".format(self.short_description, self.amount)
diff --git a/jdav_web/jdav_web/settings/components/jet.py b/jdav_web/jdav_web/settings/components/jet.py
index d860958..e261545 100644
--- a/jdav_web/jdav_web/settings/components/jet.py
+++ b/jdav_web/jdav_web/settings/components/jet.py
@@ -54,9 +54,9 @@ JET_SIDE_MENU_ITEMS = [
         {'name': 'post', 'permissions': ['startpage.view_post']},
     ]},
     {'label': 'Externe Links', 'items' : [
-        { 'label': 'Nextcloud', 'url': CLOUD_LINK },
-        { 'label': 'DAV 360', 'url': DAV_360_LINK },
-        { 'label': 'Julei-Wiki', 'url': WIKI_LINK },
-        { 'label': 'Kompass Dokumentation', 'url': DOCS_LINK },
+        { 'label': 'Nextcloud', 'url': CLOUD_LINK, 'url_blank': True },
+        { 'label': 'DAV 360', 'url': DAV_360_LINK, 'url_blank': True },
+        { 'label': 'Julei-Wiki', 'url': WIKI_LINK, 'url_blank': True },
+        { 'label': 'Kompass Dokumentation', 'url': DOCS_LINK, 'url_blank': True },
     ]},
 ]
diff --git a/jdav_web/members/admin.py b/jdav_web/members/admin.py
index 2983481..670fc0d 100644
--- a/jdav_web/members/admin.py
+++ b/jdav_web/members/admin.py
@@ -42,8 +42,9 @@ from .models import (Member, Group, Freizeit, MemberNoteList, NewMemberOnList, K
 from finance.models import Statement, BillOnExcursionProxy
 from mailer.mailutils import send as send_mail, get_echo_link
 from django.conf import settings
-from utils import get_member
+from utils import get_member, RestrictedFileField
 from schwifty import IBAN
+
 #from easy_select2 import apply_select2
 
 
@@ -230,10 +231,9 @@ class MemberAdmin(CommonAdminMixin, admin.ModelAdmin):
     list_display_links = None
     readonly_fields = ['echoed', 'good_conduct_certificate_valid']
     inlines = [EmergencyContactInline, TrainingOnMemberInline, PermissionOnMemberInline]
-    #formfield_overrides = {
-    #    ManyToManyField: {'widget': forms.CheckboxSelectMultiple},
-    #    ForeignKey: {'widget': apply_select2(forms.Select)}
-    #}
+    formfield_overrides = {
+        RestrictedFileField: {'widget': forms.ClearableFileInput(attrs={'accept': 'application/pdf,image/jpeg,image/png'})},
+    }
     change_form_template = "members/change_member.html"
     ordering = ('lastname',)
     actions = ['request_echo', 'invite_as_user_action']
@@ -788,7 +788,8 @@ class BillOnExcursionInline(CommonAdminInlineMixin, admin.TabularInline):
     sortable_options = []
     fields = ['short_description', 'explanation', 'amount', 'paid_by', 'proof']
     formfield_overrides = {
-        TextField: {'widget': Textarea(attrs={'rows': 1, 'cols': 40})}
+        TextField: {'widget': Textarea(attrs={'rows': 1, 'cols': 40})},
+        RestrictedFileField: {'widget': forms.ClearableFileInput(attrs={'accept': 'application/pdf,image/jpeg,image/png'})},
     }