There appears to be an entire industry out there trying to see who can create the most complex Shimano Di2 internal battery retention device! Rubber bands, shims, screws, washers, clips…

Engineers at Nex-Gensports have designed and produced what is undoubtedly the simplest and most effect retaining device in the market.


Made of hi-grade flexible silicon rubber these mounts:
• Will not rust or deteriorate
• Will not slip inside any suitably shaped tubing
• Both battery ends centres and secured – No battery rattle over cobbles
• Are designed to conform to regular 31.8 seatposts and most aero-shaped posts*
• Easy to install and remove without any special tools
• Low weight – Only 5.25 gms per piece
• May be trimmed to shape for aero posts if required

*27.2 round seat post design available soon