I bought the Covia Zeal Edge mini DAC Amp for use with a phone not having USB "C" as this DAC has a micro USB type input. Its constructed of metal with mat finish exterior. The input is through a micro USB cable coming out from the inside the DAC. On the other side of the DAC is the 3.5 mm jack port. Its 7/8 cm long, 2 cm wide and about 8mm high. Sides are beautifully curved and good to hold. There is a strong and sturdy spring clip marked "ZEAL" resembling a clip of a pen. The packet is excellently printed but most of the instructions is in Japanese. I bought it from ebay.com for 16 USD plus another 4/5 USD for shipping. The DAC is made in China. Initially I listened to this with my wife's Redmi 4X. It worked but somehow there was a connectivity problem and one of the channel would only play if I pulled the earphone jack a bit (about 0.5 mm) outside. I was disappointed as otherwise this device is solidly constructed and has an excellent and solid finish. Today I tried to give it a go as I was enjoying a holiday. Unscrewed the case. The PCB was tightly fitted in a channel side the case but could be pulled out easily. On opening, I found a wire hanging loose (solder failure) and the Earphone female socket not soldered properly to the board. Poor craftsmanship of such an excellent device at least from its external appearance. I soldered them and put it back and fitted the case again. Connected it to Redmi 4X, started HiBy and wow sound came out from both the channels, and what a sound it was. I was blown away. Exceptional clarity with minute details of 24/192 track hearable, open and airy, tight bass, excellent sparky treble, may be a bit sibilant and very good mids. I am loving the sound of this mini DAC Amp. I think its much better than my VE Odyssey, KZ USB C DAC Cable and at par with Hidizs Sonata 2, if not better. I feel the Covia Zeal reproduces a sound which I feel is more pleasure and lively to listen than Sonata. Wish to listen from experts who have both. Overall an excellent buy for me now after I could fix it, although the item was defective on receipt. Edit : One con which i forgot is - the device heats up quite a bit. Can hold it by hand but couple of degrees more and skin may burn.