Is weighted Stretching safe and okay?

Its nothing drastic, just a light plastic curl bar, (doesn't weigh even a pounds, with two 10lbs on each side. No challenge at all, I can throw it in the air atleast 5ft and catch it with out struggle. I was wanting to know if this is safe to use, like a lat bar to stretch my back and shoulders. It helps put a little restistance so I don't need another person.