This Columbia Sportswear Sweat Threat Polo Shirt drops from $29.99 to $23.96 at Sierra Trading Post when you use coupon code ACACAMP3 at checkout. Shipping is $5.95. This is the lowest price we found by $9. This shirt has Omni-Wick evaporation and Omni-Freeze cooling technologies that wick moisture and dry and disperse body heat quickly to keep you cool and dry. It's available in four colors, with sizes varying per color. Grill (pictured) was available in S to XL. There is no sales tax in most states.