Walmart offers the WorkChoice 50-Foot SJTW 16/3 Outdoor Extension Cord in Green or Orange for $9.97. Opt for in-store pickup to avoid the $5.99 shipping fee. That's the lowest price we could find by $9. (For further comparison, we saw the indoor version for slightly less yesterday, since expired.) This 3-wire grounded cord includes a Velcro strap for storage.