The model 7 is an all rounder designed with the professional gardener in mind.
The number 7 has an ergonomic grip and special rolling handle which turns when squeezed to drastically reduce the pressure on your wrist and the base of your thumb. Designed to reduce the chances of repetitive strain type injury and subsequent arthritis.
If you're using bypass secateurs all the time in a professional capacity then a pair such as this is highly recommended to protect yourself against unnecessary strain.
We also recommend this pair to users who already experience arthritis or similar discomfort when using secateurs.