Riff is played througout the entire song 

e|-7slide5----8--7slide5---5 ----------| 
B|---------5------------6--------------| 
G|-------------------------------------| 
D|-------------------------------------| 
A|-------------------------------------| 
E|-------------------------------------| 
  0:50 the song pauses and plays the same riff just in lower octave 

e|-------------------------------------| 
B|-------------------------------------| 
G|-------------------------------------| 
D|-9slide7----10  9slide7------9-------| 
A|---------5---------------8-----------| 
E|-------------------------------------|