Grandpa's Birthday Sudoku Challenge: Can Grandpa do 50 hard puzzles in 50 days? Hmm...
| Country | USA |
| Brand | YHXMARSCAN |
| Manufacturer | Shen Zhen Shi Yue Huo Xing Dian Zi Shang Wu You Xian Gong Si |
| Binding | Unknown Binding |
| ItemPartNumber | SN-900 |
| Model | SN-390-Green |
| Color | Blue and Green |
| ReleaseDate | 0000-00-00 |