I use jes extender at least an hour a day. Because my glans is small it slips out. Also the silicon tube must be cleaned often to keeps its texture. After 1 year it should be replaced.
I have made slight gains mostly to my FL. from maybe from 3 inches to 4 inches. Its hard to measure bc you FL changes throughout the day and based on climate temperature positioning etc etc.
I would recommend Jes extender full pack. The employees give you quick responses and will refund you if you have a legitimate claim against them. This happened to me once a few years back.
Based on my experience this device can increase FL which is important to many ppl. No effect on
Girth obviously or EL imo.
I also put velcro straps to make sure the silicon tubes stay in place. Jes extender has other items like velcro straps instead of silicon tube to secure the head of glans. DO NOT USE THIS because the velcro straps dont secure your penis very well.
Other potential struggle is if your penis slips out of the silicon tube whilst you are outside in public, it has happened to me and is a problem. Wear tight boxer briefs to avoid the extender falling off.