Yes, it comes with a lifetime warranty*.
REP Fitness will warranty these products from defects in material, functionality, and workmanship for the lifetime of the product. Lifetime warranty coverage ends when the product becomes unusable for reasons other than defects in material or workmanship. The warranty applies only to the original purchaser and is nontransferable.
REP's QuickDraw™ Adjustable Dumbbell's drop resistance cannot be permanently guaranteed. A dumbbell's resistance may be affected by the aging of materials or by an accidental shock to one of the components such as plastics and switches.
The lifetime warranty does not cover:
Wear and tear due to normal usage; e.g., scratches, dents, rust.
Any damage of any part resulting from abnormal/abusive use (consistent drops), negligence, lack of care, accidents (drops/dings), incorrect use and/or operation of the dumbbell as specified in the user manual by REP.