PRINCIPLE : The forced-feed rock breaker is built entirely of steel with the exception of the two flywheels. It is only one-third the weight of a cast-iron rock breaker of the same size. The crusher operates on heavy duty roller Bearing, which are well sealed against dust and oil and require oil replenishment once every six months. The Crusher can also handle damp material that would clog the ordinary rock breaker. This is on account of the down-stroke of the Jaw and the sudden backward movement at the end of the stroke. The manganese toggle is fitted with an oil reservoir, which feeds the oil to the toggle through a wick. The feed adjustment of the crusher is on the outside, and adjustment can be made while the crusher is in operation and without any danger to the operator. Jaw Crusher is available in single or double toggle arrangements.