For as long as possible:

From 0:00-3:00
  2 rounds of: 
  10 overhead squats (95 / 65 lb.)
  10 chest-to-bar pull-ups

From 3:00-6:00
  2 rounds of:
  12 overhead squats (95 / 65 lb.)
  12 chest-to-bar pull-ups

From 6:00-9:00
  2 rounds of:
  14 overhead squats (95 / 65 lb.)
  14 chest-to-bar pull-ups

Etc., following same pattern