Product Development Story | Pentagon Large

Responding to calls for "lighter, yet larger." The ultimate 54cm.

Folding umbrellas present a challenge: "choose lightness, and it's small; increase the size, and it becomes heavy." While the lightness of its predecessor, pentagon72, was well-received, we received many requests for a larger size that could also adequately protect a bag.

Initially, we considered ribs of 60cm, but with only five ribs, the structural balance would be compromised, and adding more ribs would sacrifice lightness. After extensive testing, we arrived at "54cm ribs, 85cm diameter" as the limit for maintaining lightness while clearing a wind resistance test of 15m/s (※fixed at 0 degrees environment).

Due to its structure, a 5-rib umbrella without diagonal ribs tends to have a shorter diameter. However, the difference in area compared to a 6-rib umbrella with the same rib length is only about 8.5%. It was by sacrificing this slight difference and completely shedding "the weight of one rib" that we were able to achieve a practical breadth while maintaining a lightness of "approx. 79g." This is the result of pursuing actual usability and the practical benefits of lightness, without being constrained by unfavorable numbers.

Furthermore, it is also slim at approximately 3.5cm wide and offers the convenience of being temporarily bundled like a long umbrella without fully folding it when on the move. Without being constrained solely by numerical specifications, this "pentagon LARGE" was developed by thoroughly pursuing a balance between actual usability and portability. It delivers the comfort of being able to easily put it in your bag and go out unencumbered, even on days with unpredictable weather.