Muqan Qaghan

Muqan Qaghan; (Old Turkic: , Muqan qaγan,Chinese:木桿可汗/木杆可汗, Pinyin: mùgǎn kěhàn, Wade-Giles: mu-kan k'o-han or 木汗可汗, mùhàn kěhàn, mu-han k'o-han, personal name: 阿史那燕都, āshǐnà yàndōu, a-shih-na yen-to) was the second son of Bumin Qaghan and the third khagan of the Göktürks who expanded their khagan and secured the borders against the Hephthalites.

...
Wikipedia