I am writing to you 1 the digital recording pen which I bought from your shop. I would like to return it and request for a full refund. Last week, I bought a digital recording pen 2 your store. But when I checked it 3 myself at home, unfortunately, I found that there's something wrong with it. The voices recorded by your recording pen arenot clearly. Then I ran to your shop and asked for help. What’s worse, yourshop assistant told me that’s because the recording environment was noisy andthey refused 4 change a new one or refund. So I had to ask an expert to testify it. The test report shows that the quality of the recording pen is below-average, so I have to write this letter to you and ask you 5 your response.