I would not call it 100% gluten free. It may have been processed in a facility that processes wheat or other gluteny items. As far as the rice syrup solids go, it doesn't naturally contain gluten. I have never had a problem with them. You should be ok.
For anyone that might be interested, I received a response from the company. The Rice Syrup Solids packaged by Crosby & Baker if from California Natural Products. I've attached their gluten free statement.