Five (5) high quality, plastic pulleys with 50 mm diameter, each on an open sided steel frame, with hooks at each end. Pulleys are of a low-friction, ball bearing design. The open sided frame greatly facilitates stringing up as no 'threading' is involved.
This set of pulleys is very useful in the classroom to perform many different experimental set-ups investigating Newton's Force Laws.
Inner gap of pulley measures 3 mm, overall length of 9.8 cm. Each capable of holding over 30 lbs in weight.