Ronstan RF35109HL High Load 30mm Orbit Block. The RF35109HL has a maximum line size of 8mm and is rated to 550kgs (1210lbs) Maximum Working Load and 1650kgs (3630lbs) Breaking Load. The Breaking Load is dependent on the strength of the lashing through the central hub. The hub can also double as a becket take off point. We use this block for one of our advanced kicker/vang top block solutions.