When sourcing wholesale jeans, the fabric weight (measured in ounces) is the primary indicator of quality. For standard men's jeans, look for 12oz to 14oz for durable, high-quality denim, while 8oz to 10oz is suitable for lightweight summer collections. Ensure the composition matches your market needs: 100% cotton for authentic vintage feel, or 98% cotton and 2% spandex (elastane) for the popular 'stretch' fit. Always request a GSM (Grams per Square Meter) report to verify density and prevent receiving thin, low-grade material.