To determine if your supplier is reliable for supplying aluminum sheets, consider the following: Check their track record and customer reviews for consistency and quality. Assess their industry certifications, such as ISO standards, which indicate commitment to quality management. Evaluate their supply chain transparency and their ability to meet delivery timelines. Look into their financial stability to ensure they can sustain operations. Request samples to test the quality of their aluminum sheets. Finally, communicate openly with them to gauge their responsiveness and professionalism.