1. X217 is well designed with sturdy feeling and comfy in the hands. The carbon fibre is the most delicate part of it and also helps to stop it feeling like a bar of soap and slipping out of hands! Made with high quality, it shows no signs of scratches and won’t show up finger prints which is very friendly to people with sweaty hands! Quoted from Purplefowler 2. X217 mod doesn't instantly turn on when batteries are inserted. You can chucked batteries in and pocketed it but it won’t auto fire. It’s safer to keep. 3. Hits hard and instant with 21700 which can offer the best vaping experience for vapers. 4. Dual 21700 batteries and well-know with really good battery life.