Name one thing.No lists or seconds.What could you not do with out on a Hunt.This will be a piece of gear,not a gun or clothes. For me it`s a Rangefinder.I have no ability to judge distance after 150 yards.
For the timbered and brushy areas I commonly hunt a GPS has been the most important improvement. It has saved me miles of flagging tape. I do have a range finder but have few reasons to use it.
