This product is very easy to put on the seat belt, just unsnap the snap, pull the seat belt through, and re-snap the snap, bam done, no directions required.
My daughter loves it because the seat belt no longer rests on her throat and I love it because she's no longer begging to put the belt behind her back. The seat belt adjuster pad pulls the seat belt down and slightly away, alleviating the uncomfortable set belt rub, but still providing full seat belt protection.
The only downfall that I found, is that it slips down and covers the top buckle, making it very hard for my daughter to buckle her own seat belt, otherwise it's perfect.
I would fully recommend this product to anyone who has a child that uses a seat belt.
I received this product at a discounted price in exchange for an honest review, my opinions are my own.