A shipping tray or pallet which can serve either as a top or bottom support tray for a shipping container that allows for nesting of one or more trays so that only a minimum amount of space is required when returning empty trays and an improved method for interlocking foot portions or legs of two stacked trays so that safer and more stable stacking is possible and lateral shifting of one tray with respect to another when in a stacked configuration is prohibited. Each of the foot portions of the trays is provided with male and female reinforcing ribs which will interlock with complementary legs on a similarly designed tray.