simply the best cylinder out there!
First off I have over 15 years experience on this device. The only choice for high rise repealing, the bottom lock off is incredible on buildings 40 to 50 stories high, so much better then a rack, it saves me so much energy and arm fatigue. single lock off is good for 20 and up. double lock for 20 and down. the only draw back to cylinders is that there is a birds nest at the bottom if there is too much rope on the ground. it creates a lot of twist.