Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Sturdy, No Flexing, Some Flashing on Seams

I needed this pyramid mold for resin casting, and it is very sturdy and won't flex, excellent for casting. The chrome surface releases easily from fiberglass resin with a little mold release compound or spray oil. The mold does have some welding flashing on the inside seams, so you won't get a flawless cast, but it can be sanded clean.