Walmart offers the Samsung 64GB EVO UHS-I Class 10 microSDXC Card with Adapter, model no. MB-MP64DA/AM, for $18.74. (Amazon has it for the same price.) Opt for in-store pickup to dodge the $4.97 shipping fee. That's $2 under our mention from two days ago and tied as the best price we've seen. (It's also a current low by $5.) It features data transfer speeds of up to 48MB/s.