Box Two Prime 9 X-Wide 11-50T Cassette
The Box Two cassette was where Prime 9 started. Originally conceived as an E-MTB product to deliver long service life and extra range over fewer gears, we quickly grew to enjoy its abilities on unpowered MTBs. All cogs are stamped from steel and subsequently, the larger ones are pinned to alloy spiders. Due to its provenance, this is, without doubt, the most durable cassette in the range.
Another excellent component
I own many BOX Prime 9 systems. 1, box One Two system, 1, box Two system, 1, box Two Three system and 1, box Three system. This purchase was to complete a new BOX Two system for a 2019 Trek Marlin 4 that's been so upgraded it's now better than a 2022 Trek Roscoe 8, and part of that is a complete BOX Prime 9 Two system. Keep making great components.
Best performance/value cassette
5 star operation. I am completely sold on Prime 9
Heavy but still the best cassette range for 1-by conversions
This was used for a 1-by conversion of my 2009er Haibike Edition hardtail and it was the best upgrade since I've gone tubeless on this bike. Two important lessons learned: 1. Make sure your rear derailleur has enough capacity to serve a 50T cassette. I had to order the Box Two Prime 9 XL-cage derailleur (and Box One Prime 9 shifter) since my existing derailleur couldn't handle anything bigger than a 34T cassette. Both the shifter and derailleur are excellent, but keep the additional cost in mind. 2. Pay attention to your chainline - bigger rings in the front might need more spacers / offset than you expect. I ended up using 9.1 mm(!) spacers to get the chain line and noise in check using a 34T ring on a 104 BCD crankset. For an every-day MTB, my recommendation would be to pair this cassette with a 34T oval chain ring in the front, which will give you marginally improved climbing without loosing too much top speed when compared to the classic 3-by system (44/32/22 rings with an 11-32 cassette). If you're bikepacking, consider a 30T oval chain ring to get even better climbing. In my experience the oval chain ring will provide you with a wider usable cadence range (when compared to round chain rings), which compensates nicely for the loss in granularity by dropping 18 gears. So far, I've put around 900 miles on the cassette in six months on my bikepacking commuter. Shifting is still great, surface wear appears nominal. I like the old-school construction cogs hardest five gears, because this is where most of the wear and tear accumulates. Since shipping from the US to Germany is crazy expensive due to ~30 % import tax I hope to be able to replace the smaller cogs with locally sourced parts instead of ordering a complete replacement cassette once this ones worn out. My only complaint would concern the weight of the cassette, which comes in around 645 g on my scale. It's not exactly a drag, but you definitely feel the weight of your drivetrain with this piece.
Box 2 cassette is tough a light for Pisgah
Super tuff, long lasting and sharp