diff --git a/extensions/cmp/cmp_custom_vendor_mapping.js b/extensions/cmp/cmp_custom_vendor_mapping.js
index a1ed2d98..7f69e66d 100644
--- a/extensions/cmp/cmp_custom_vendor_mapping.js
+++ b/extensions/cmp/cmp_custom_vendor_mapping.js
@@ -58,7 +58,9 @@
     const domainTagValues = {
         piano: {
             bild: [16],
+            springpremium_bild:[130],
             welt: [230],
+            springpremium_welt:[68],
             fitbook: [43],
             myhomebook: [46],
             petbook: [83],
@@ -81,7 +83,9 @@
         },
         googleAds: {
             bild: [21],
-            welt: [147]
+            springpremium_bild:[57],
+            welt: [147],
+            springpremium_welt:[77]
         },
         nielsenAgf: {
             welt: [251],
@@ -94,7 +98,7 @@
         },
         kilkaya: {
             welt: [298],
-        }
+        },
     };
 
     function getDomainTagValue(domain, vendor) {
@@ -286,4 +290,4 @@
         init();
     }
     
-})();
+})();
\ No newline at end of file
diff --git a/extensions/kilkaya/k5a_meta_conversion.js b/extensions/kilkaya/k5a_meta_conversion.js
new file mode 100644
index 00000000..f2331dae
--- /dev/null
+++ b/extensions/kilkaya/k5a_meta_conversion.js
@@ -0,0 +1,36 @@
+/* Pre Loader — k5aMeta conversion for checkout success */
+/* global utag, a, b */
+/* eslint-disable-next-line no-unused-vars */
+(function (a, b) {
+    try {
+        if (String(b.event_name) !== 'checkout' || String(b.event_action) !== 'success') {
+            return;
+        }
+
+        // Ensure meta object exists
+        if (!window.k5aMeta || typeof window.k5aMeta !== 'object') {
+            window.k5aMeta = {};
+        }
+
+        // Mark conversion (Kilkaya conversion flag)
+        window.k5aMeta.conversion = 1;
+
+        // Prepare cntTag array
+        if (!Array.isArray(window.k5aMeta.cntTag)) {
+            window.k5aMeta.cntTag = [];
+        }
+
+        if (b.offer_id) {
+            window.k5aMeta.cntTag.push('offer_' + String(b.offer_id));
+        }
+
+        if (window.utag && window.utag.cfg && window.utag.cfg.utDebug) {
+            utag.DB('k5aMeta conversion set for checkout success');
+        }
+
+    } catch (e) {
+        if (window.utag && window.utag.cfg && window.utag.cfg.utDebug) {
+            utag.DB('k5aMeta conversion error: ' + e);
+        }
+    }
+})(a, b);
diff --git a/tests/kilkaya/k5a_meta_conversion.test.js b/tests/kilkaya/k5a_meta_conversion.test.js
new file mode 100644
index 00000000..7d9e00d3
--- /dev/null
+++ b/tests/kilkaya/k5a_meta_conversion.test.js
@@ -0,0 +1,366 @@
+/**
+ * @jest-environment jsdom
+ */
+
+describe('k5a_meta_conversion', () => {
+    let originalUtag;
+
+    beforeEach(() => {
+        // Clean up window.k5aMeta before each test
+        delete window.k5aMeta;
+        
+        // Save original utag if it exists
+        originalUtag = window.utag;
+        
+        // Mock utag
+        window.utag = {
+            data: {},
+            cfg: {
+                utDebug: true
+            },
+            DB: jest.fn()
+        };
+
+        // Clean up global variables
+        delete global.a;
+        delete global.b;
+    });
+
+    afterEach(() => {
+        // Clean up
+        delete window.k5aMeta;
+        if (originalUtag) {
+            window.utag = originalUtag;
+        } else {
+            delete window.utag;
+        }
+        delete global.a;
+        delete global.b;
+        jest.resetModules();
+    });
+
+    it('should set conversion flag and cntTag for checkout success event', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: '12345'
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta).toBeDefined();
+        expect(window.k5aMeta.conversion).toBe(1);
+        expect(Array.isArray(window.k5aMeta.cntTag)).toBe(true);
+        expect(window.k5aMeta.cntTag).toContain('offer_12345');
+        expect(window.utag.DB).toHaveBeenCalledWith('k5aMeta conversion set for checkout success');
+    });
+
+    it('should not set conversion if event_name is not "checkout"', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'other_event',
+            event_action: 'success',
+            offer_id: '12345'
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta).toBeUndefined();
+        expect(window.utag.DB).not.toHaveBeenCalledWith('k5aMeta conversion set for checkout success');
+    });
+
+    it('should not set conversion if event_action is not "success"', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'failure',
+            offer_id: '12345'
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta).toBeUndefined();
+        expect(window.utag.DB).not.toHaveBeenCalledWith('k5aMeta conversion set for checkout success');
+    });
+
+    it('should initialize k5aMeta object if it does not exist', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: '12345'
+        };
+
+        expect(window.k5aMeta).toBeUndefined();
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta).toBeDefined();
+        expect(typeof window.k5aMeta).toBe('object');
+    });
+
+    it('should preserve existing k5aMeta properties when setting conversion', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: '12345'
+        };
+
+        window.k5aMeta = {
+            existingKey: 'existingValue',
+            url: 'https://example.com'
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta.existingKey).toBe('existingValue');
+        expect(window.k5aMeta.url).toBe('https://example.com');
+        expect(window.k5aMeta.conversion).toBe(1);
+    });
+
+    it('should initialize cntTag array if it does not exist', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: '12345'
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(Array.isArray(window.k5aMeta.cntTag)).toBe(true);
+        expect(window.k5aMeta.cntTag.length).toBe(1);
+    });
+
+    it('should append to existing cntTag array', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: '67890'
+        };
+
+        window.k5aMeta = {
+            cntTag: ['existing_tag']
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta.cntTag).toEqual(['existing_tag', 'offer_67890']);
+    });
+
+    it('should not add offer tag if offer_id is missing', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success'
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta.conversion).toBe(1);
+        expect(Array.isArray(window.k5aMeta.cntTag)).toBe(true);
+        expect(window.k5aMeta.cntTag.length).toBe(0);
+    });
+
+    it('should handle offer_id as number', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: 99999
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta.cntTag).toContain('offer_99999');
+    });
+
+    it('should convert offer_id to string when creating tag', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: { toString: () => 'special_id' }
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta.cntTag).toContain('offer_special_id');
+    });
+
+    it('should handle non-array cntTag by replacing it with an array', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: '12345'
+        };
+
+        window.k5aMeta = {
+            cntTag: 'not_an_array'
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(Array.isArray(window.k5aMeta.cntTag)).toBe(true);
+        expect(window.k5aMeta.cntTag).toContain('offer_12345');
+    });
+
+    it('should handle null or undefined b parameter gracefully', () => {
+        global.a = 'some_value';
+        global.b = null;
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta).toBeUndefined();
+    });
+
+    it('should handle errors gracefully and log them', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: '12345'
+        };
+
+        // Force an error by making window.k5aMeta read-only
+        Object.defineProperty(window, 'k5aMeta', {
+            value: null,
+            writable: false,
+            configurable: true
+        });
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.utag.DB).toHaveBeenCalledWith(expect.stringContaining('k5aMeta conversion error:'));
+
+        // Clean up the read-only property
+        delete window.k5aMeta;
+    });
+
+    it('should handle missing utag gracefully', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: '12345'
+        };
+
+        delete window.utag;
+        global.utag = undefined;
+
+        // With the guard in place, the code should not throw even if utag is missing
+        expect(() => {
+            require('../../extensions/kilkaya/k5a_meta_conversion.js');
+        }).not.toThrow();
+
+        // The conversion should still be set
+        expect(window.k5aMeta).toBeDefined();
+        expect(window.k5aMeta.conversion).toBe(1);
+        expect(window.k5aMeta.cntTag).toContain('offer_12345');
+    });
+    it('should work when utag is defined but utag.data is missing', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: '12345'
+        };
+
+        window.utag = {
+            DB: jest.fn()
+        };
+        // utag.data is undefined
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta).toBeDefined();
+        expect(window.k5aMeta.conversion).toBe(1);
+        expect(window.k5aMeta.cntTag).toContain('offer_12345');
+    });
+
+    it('should handle event_name and event_action type coercion', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: { toString: () => 'checkout' },
+            event_action: { toString: () => 'success' },
+            offer_id: '12345'
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta.conversion).toBe(1);
+        expect(window.k5aMeta.cntTag).toContain('offer_12345');
+    });
+
+    it('should handle empty offer_id', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: ''
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta.conversion).toBe(1);
+        expect(window.k5aMeta.cntTag.length).toBe(0);
+    });
+
+    it('should handle offer_id with special characters', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: 'special-offer_123@test'
+        };
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta.cntTag).toContain('offer_special-offer_123@test');
+    });
+
+    it('should not log when debug mode is disabled', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: '12345'
+        };
+
+        window.utag.cfg.utDebug = false;
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.k5aMeta.conversion).toBe(1);
+        expect(window.utag.DB).not.toHaveBeenCalled();
+    });
+
+    it('should not log errors when debug mode is disabled', () => {
+        global.a = 'some_value';
+        global.b = {
+            event_name: 'checkout',
+            event_action: 'success',
+            offer_id: '12345'
+        };
+
+        window.utag.cfg.utDebug = false;
+
+        // Force an error
+        Object.defineProperty(window, 'k5aMeta', {
+            value: null,
+            writable: false,
+            configurable: true
+        });
+
+        require('../../extensions/kilkaya/k5a_meta_conversion.js');
+
+        expect(window.utag.DB).not.toHaveBeenCalled();
+
+        // Clean up
+        delete window.k5aMeta;
+    });
+});