UPDATE 2 November 25th, 2018: Almost two months later after only being used once this item is officially dead. I mentioned last time the pump didn't work , but I somehow managed to revive her. No luck this time. I'm just glad I didn't rely on it in my hour of need and found it was out of service during scheduled bike maintenance. The part is almost new, but the pump does not start. This is a strange bug. Regardless, it goes on the returned stack. Thankfully, Revane accepted it for a full refund even though the return window had passed. Your luck may not be so good. Buyer Warning. This thing will annoy you whether you use it often or not, and it can irritate you at the most inopportune moment. Don't count on it. Buy something from a reputable brand. UPDATE: Well, Fineed contacted me and sent me a new pack of pump adapters. I received it in about 2 weeks. They look ok although I haven't checked. I changed my review and rating due to their good service. I'll leave it at 4/5 for now though. Why: The pump hasn't worked lately. I was doing a regular service and decided to inflate the tires on my bike. Unfortunately, the power button didn't work. Although the 'Unit' button worked, turning on the screen and allowing me to set the PSI, I could not get the pump to work in PUMP mode. I plugged it in to charge, which was quick, so I'm assuming the battery is already fully charged. Still couldn't. It wasn't until I played with the power button a few times that it finally pumped. The button seems finicky and in the "pressed" position it's technically "off". I'll keep a closer eye on it when I use it again in the next few weeks (it's pretty cold here). Another note - the pump is off by about 1psi. I suggest setting PSI 1 lower than intended as the device will pump. All in all, this is a practical product. I love that it specifically fits my tool tube for my motorcycle while no other portable pump fits. OLD: The Presta adapter is not well made. In my photo you can see the imperfection of the neckline at the opening. Due to this defect, the O-ring slips easily when pumping (see second photo). The only solution is to buy a different, better quality Presta adapter for the included Schrader valve.