Glide castors

A glide castor comprising a lower moulding with a convex bottom ground-engaging surface, said lower moulding having an integral upstanding boss with a bore for a mounting spindle, and an upper cap-like moulding which seats on a peripheral seating on the lower moulding, said upper moulding being formed for snap-on engagement with said upstanding boss of said lower moulding thereby to hold the lower and upper mouldings together as a two-part body assembly;

• wherein said upper moulding is a shell of substantially uniform thickness apart from a region of the upper moulding surrounding and which snaps on to said upstanding boss fo said lower moulding;
• and wherein said region of the upper moulding is formed as an interval boss of annular form and constant wall thickness, said interval boss fitting closely around said upstanding bass of said lower moulding.