This umbrella base looks attractive but it is not stable enough as a free standing umbrella holder.  It tips over when there is any slight breeze.  The base comes with just one nut to attach the bottom to the stem and it is impossible to get tight enough to be secure, so the umbrella wobbles in the base.  I would not recommend this product if using it for a free-standing umbrella.  It would probably fine if using under a table, though.