Instruct: Classify Amazon reviews into positive or negative sentiment
Query: At Last, an Adjustable Clamp

It's a gamble buying tail lights because seat post size varies so much. Mine is a largish 31.8mm, and most lights won't fit. This light has a plastic 'radiator hose' style adjustable clamp. I didn't use (or need) the soft rubber spacers included with the light, and because of that it slips on the seat post. A little bit of electrical tape under the clamp should take care of that.It doesn't shine to the sides as much as I'd like.One nice thing is the on/off button: You don't have to cycle through the different flash patterns to get to "off". One long hold on the button turns it off, or turns it on to the last used flash pattern.