MEGADETH bassist David Ellefson has posted behind-the-scenes footage from his three clinic appearances (October 11-13) for Hartke at the ProLight & Sound event in Shanghai, China. Check out the seven-and-a-half-minute clip below.In addition to numerous gold and platinum records and eight Grammy-nominated works, David is the author of the book "Making Music Your Business" and has two metal bass guitar instructional DVDs through Rock House Method entitled "Metal Bass Vol. 1" and "Vol. 2". He is also a featured bass clinician, keynote speaker and panelist on the subject of music and the music industry. The 20th-anniversary edition of MEGADETH's 1992 double platinum-certified "Countdown To Extinction" album will be released on November 6 via Capitol/EMI. After wrapping up their "TH1RT3EN World Tour" this fall, MEGADETH will perform the acclaimed album in its entirety on their "Countdown To Extinction 20th Anniversary Tour" this November and December. Presented in a 2CD lift-top box and digitally, "Countdown To Extinction"'s new commemorative edition pairs the remastered original album with a 1992 concert, recorded live at San Francisco's Cow Palace, which has never before been released in its entirety. The concert audio has been newly remixed for this release. The physical and digital versions both include a booklet with a new liner notes essay by music journalist Kory Grow, and the 2CD box also contains a 24" x 36" poster and four collectible postcards.