The dumbbell, a type of free weight, is a piece of equipment used in weight training. It can be used individually or in pairs, with one in each hand.A barbell is a piece of exercise equipment used in weight training, weightlifting and powerlifting. Barbells range in length from 4 feet (1.2 m) to above 8 feet (2.4 m), although bars longer than 2.2 metres (7.2 ft) are used primarily by powerlifters and aren't commonplace. The central portion varies in diameter from 25 millimetres (0.98 in) to even 2 inches (51 mm), LinoSports provide various kinds of dumbbells and barbells for gym owners or gym equipment dealers, there must be some thing you are interested in.