SRD:Net of Snaring

Net of Snaring: This net provides a +3 bonus on attack rolls but can only be used underwater, thus making it a somewhat useful item rather than what most would really call a cursed item. Underwater, it can be commanded to shoot forth up to 30 feet to trap a creature.

Moderate evocation; CL 8th; Craft Magic Arms and Armor, freedom of movement; Price 10,000 gp.