Good product but DO NOT follow the instructions too closely. If you do then the resulting mix will be too 'wet' resulting in a soft crumbly surface when set. For best results mix to a thicker consistency BUT the setting time is vastly reduced. Preparation is key and be very ready to place the mix exactly where needed before it sets. The resulting filling will be very hard & durable. I worked in dentistry as a Dental Technician for 40 years, now retired.