Sometimes a new company launches a product, sends a sample, and when I open the box I’m surprised when I see what’s inside. Such was the case with the Rinsten Spring Ultimate Bicycle Shock Absorber that I’m covering here. From what Rinsten wrote about the product in their email, I envisioned a typical telescoping seatpost or a post with suspended seat clamp. Over the years there’ve been many designs like this and some are still on the market. But I wasn’t expecting Rinsten’s simple bent-wire spring suspension.