I held these pens for about an hour before the round part started to slip and buckle. I noticed that the adhesive pads started slipping out from the bottom (see photo). He also managed to scratch my gimbal. Also, I almost dropped my $2,000 camera because of the poor grip design. The handles are screwed on so I made a very simple move and grabbed it with one hand, the handle unscrewed and I almost dropped everything. My heart sank into my stomach... luckily nothing hit the ground, but it was too close for me. I get stronger grips. They don't cost $130. Returned immediately.