TomTop offers the RD UM24C USB 2.0 Color LCD Display Tester for $20.99. Coupon code "UM245" drops it to $15.99. With free shipping, that's the lowest price we could find by $2. It features an LCD display and can be used to test devices for voltage, current, power, capacity, and storage.

This item ships from China and may take up to three weeks to arrive.