When sourcing for agriculture (Super Absorbent Polymer or SAP), the most critical metric is the water absorption capacity, which should typically range between 300 to 500 times its own weight in deionized water. You must also verify the particle size distribution (e.g., 0.5–2.0 mm) to ensure it matches the soil type and application method. Additionally, ensure the product is Potassium-based (Polyacrylate Potassium) rather than Sodium-based, as sodium can lead to soil salinization and toxicity for plants.