The new ISC 200 Series pulleys feature a Safelock mechanism and are designed to improve the strength and performance of your favorite arborist blocks. These are made from high-quality aluminum frames that are designed to withstand the forces that your blocks will throw at them. The unique design of the frame and axle also helps improve the overall strength of these pulleys.

The Safelock system is a patent pending design that features a low profile and a quick opening action.