Spring tools balancer from 1KG to 400 KG. Spring balancer from 1 KG to 3 KG, model is HP1-3,min load is 1kg,max load is 3kg,stroke is 3 meters. Net weight is 1.5kg More information about spring balancer parameters, price, structure, instruction,feature please contact:www.cargotrolley.com. liftingtool@gmail.com Our website:www.cargotrolley.com