To celebrate reaching the 10,000 member milestone on their fancafe, the members of HALO courageously stood on top of a bungee jump tower to keep their promise to fans. 

OOON stated in the video, "Lets not think of this as a pledge for 10,000 members, but as us keeping our promise to our fans. And we're going to continue reaching up to 20,000~30,000 members!" 

SEE ALSO: Lee Young Ja finds love after 35 years in the industry, confirming romance with Hwang Dong Joo

In addition to thanking their fans for the support and love, the boys of HALO overcame their fears and jumped off the 45m (approximately 150 ft) high bungee jumping tower. 

Meanwhile, Yoondong and OOON opted out due to their health issues, but promised that they would fulfill the promise on a later date.

Check out the video above!

Tip: SixHalo