The HS151DR-84137120 is a DIN-rail mountable heat sink designed to accommodate single or dual solid state relays (SSRs) with excellent thermal management capabilities. It features a thermal resistance of 1.5°C/W and is constructed from black anodized aluminum, providing both durability and efficient heat dissipation across a surface area of 138 in² (891 cm²). The heat sink accepts mounting of fans up to 40 mm and includes two 8-32 UNC threaded holes for secure SSR attachment with a recommended torque of 15-20 in·lbs (1.7-2.2 nm). With a weight of 0.92 lbs (350 grams) and dimensions of 3.82 × 1.88 × 3.74 inches (97.0 × 47.7 × 95.0 mm), this component is ideal for industrial control applications requiring reliable thermal management in compact DIN-rail enclosures.