Via the screw.
value of smith & Wesson model 5906 pistol
check at: http://stevespages.com/page7b.htm
100-450 USD
50-500 usd
200-800 usd
1990
50-450 usd
100-450 usd
50-550 usd
50-400 usd
Depending on condition, around $450-$500.
Ranges $299 - $350 in pristine condition with box and papers