Description: Total head developed by the pump at a rate of flow corresponding to the best efficiency; Name: Optimal head
Description: Total head developed by the pump at a rate of flow corresponding to the best efficiency; Name: Optimum head
Description: extent of protection provided by an enclosure against access to hazardous parts, against ingress of solid foreign objects and/or ingress of water and verified by standardized test methods, expressed as a IP rating; Name: degree of protection