The above image features the "Complete Home Economics Service in the modern Century Test Kitchen." It comes from the Guardian Tested Recipes cookbook.
It shows the "Century Test Kitchen where Guardian Service recipes are developed and tested under the direction of Betty Gay, Home Economist. Guardian Service users are invited to write Betty Gay for special recipes or help with any cooking problems."
The guarantee states that "Guardian Service - America's Finest Kitchen Equipment is guaranteed not to warp, crack, buckle, or burn through when used as directed. Guardian Service is manufactured from an alloy of the finest materials available. Its base is aluminum and is guaranteed pure and safe for health. With reasonable care Guardian Service will give continuous service and satisfaction. Any units showing evidence of faulty workmanship or manufacturing defects will be replaced without charge."