Dahon specicfic extended seatpost. Fits all 16 and 20 inch bikes. It has a quick release so you can easily lower the seatpost and make the fold more compact. Maximum extension length with the supplied 27.2 regular seatpost at the upper end is 650 mm or roughly 25 3/4 inches. One could replace the upper regular road style seatpost with a longer MTB seatpost in 27.2 mm dia. The supplied upper part regular seatpost is 270 mm long. This is also a great upgrade if you want to use a regular saddle versus the I-beam saddle.
Total weight is 630 grams. The lower unit with quick release is 430 grams. The top “regular” seatpost is 260 grams.
for comparing purposes only the regular post is 524 grams