Very friendly people. Even after problem with customs sainsmart compensated big part of the taxes

Seems to be quite well-built; looking forward to see how long it's gonna last in my test setup for doing power cycle tests of embedded devices. Use of standard components (FT245RL) makes it easy to control from Linux. There a two drawbacks that could be addressed in future revisions or products: 1. Like hinted at in the description, the relays glitch during boot-up. This happens even with a USB power supply instead of the PC, so it's not a driver issue. Using an additional latch may help. 2. The board looks like it would fit a DIN rail case nicely, it even has the connectors placed appropriately. Unfortunately it barely does NOT fit: the two connector rows are a few millimeters too wide apart. Having USB and power supply on the sides would have been acceptable (though not perfect), but the 93mm are about the size of the case itself make it impossible to fit. It's good enough for my own test setup, but because of these two issues I can't recommend it to my customers. Their test equipment is mounted on DIN rails and the relays may be wired in ways where glitches may cause short-circuits.

The relay arrived in good condition and it's very well-built. I did some basic test on it, and so far no problem with it. I am searching some example code for it, but didn't have much luck. I contacted the support, and they gave me a link, where includes windows software examples. I really like this relay.