Chain, Weighted (3.5e Equipment)
From D&D Wiki
This is a chain with a weight attached to each end.
A weighted chain has reach, so you can strike opponents 10 feet away with it. In addition, unlike most other weapons with reach, it can be used against an adjacent foe.
You can make trip attacks with the chain. If you are tripped during your own trip attempt, you can drop the chain to avoid being tripped. Additionally, you get a +2 bonus on the attack roll for the trip.
When using a weighted chain, you get a +2 bonus on opposed attack rolls made to disarm an opponent (including the roll to avoid being disarmed if such an attempt fails).