A differential 4 channel, 50 MHz USB oscilloscope from TiePie engineering.
The Handyscope HS4 DIFF is a 4 channel differential USB oscilloscope with a maximum sampling speed of 50MS/s and 128 KSamples memory per channel. The differential input channels enable safely measuring, without risk of creating a short circuit through the oscilloscope. The Handyscope HS4 DIFF is delivered with a complete measurement software package that offers all you need for your measurement applications.