This is a very cheap plastic bass recorder: less than half the price of the plastic bass recorders that are produced by the major Japanese names in plastic recorders.
Having read some positive comments on this website about the Thomann bass recorder, I took the plunge and ordered one.
Unfortunately, the case of the first recorder that Thomann sent me arrived with a broken zip. I sent it back and was sent a replacement. That recorder arrived badly-scratched and with damage to the end of the windway - and the zip on the second case didn't work properly either. I sent that recorder back too and got a refund.
If you are lucky enough to get one that is unscratched, these recorders look fine from a distance. Close-up, however, it becomes apparent that the finish is poor. The plastic seams are roughly-finished. The plastic around the keys on the two examples I have seen looked as if they had been gouged by the screwdriver that was used to fit the keys. It looked as if these recorders had been hastily-assembled, with poor quality control in the factory. The case in which the recorders come has a very weak zip (the zips were broken on both examples that I have seen).
On a more positive note, I did try playing the first recorder that I was sent. It sounded fine and played all the notes that you would expect it to without any problems. These are certainly usable recorders, if not particularly high-quality ones.
I would sum up by saying that if price is more important to you than quality, this could be the bass recorder for you - it is VERY cheap. However, if you care about the quality and appearance of the musical instruments that you play and are not willing to put up with the faults that I have outlined above, I'd recommend that you do as I eventually did: stump up the extra cash and buy a bass recorder made by one of the well-known Japanese brands. There is a big difference in quality between the two. But given that this Thomann bass recorder is less than half the price of the well-known Japanese brands, it will probably suit some people down to the ground.