Supporting cars on pinch-weld rails creates excessive pressure points which can gouge or tear the standard rubber blocks and damage delicate body rails on unibody vehicles. QuickJack’s urethane rubber pinch-weld blocks were engineered with a cross-cut slotted design, allowing you to position them lengthwise or crosswise. They’re the perfect body cradling tool to safely support rocker panels or sheet metal body rails, especially pinch-weld rails that have degraded over time due to corrosion from grime and road salt. Increase safety and ensure a more stable lift with these specially designed low-profile jack pads that can be used independently or stacked on top of the standard rubber blocks. Stop using blocks of wood, hockey pucks or towels that can slip or tear, resulting in vehicle damage or worse, unstable lifting. Durable urethane rubber is impermeable to oil, grease and gas and will last a lifetime.