From the manufacturer

The FR 541 may not be your first rim, but it aspires to be the last. The new rim shape improves the impact resistance, enabling you to push a little harder on the trails. It also enhances the pinch flat protection for a trusty ride on rougher tracks. Build this rim with care and it will reward you with resistance and lightness for a long-lasting bond.

Features

• Pinchflat protection: 
  Tests conducted with a leading tire supplier showed a 17% increase in pinch flat resistance compared to the previous FR 560 rim. 
• PHR system: 
  The PHR system increases the load-bearing surface of the nipples on the rim and reduces localized stress. 

Specifications

• Net Weight: 570g
• ASTM Classification: 5
• Approved for E-bikes: Yes (max. 32Km/h or max. 
• Color: Black
• Material: Aluminum
• Rim Joint: Welded
• Tire Interface: Hooked / crotched tubeless 
• Brake Interface: Disc
• Dimensions: 27.5"
• Reference Diameter ERD: 565mm
• Inner Width: 30mm
• Outer Width: 35mm
• Rim Height: 21mm
• Holes: 28
• Spoke Bore Rim: Non eyelet PHR
• Valve Hole: Presta