The Profile Design Sonic/Ergo/39a combines the low-weight Sonic bracket with Ergo armrests and the A-Series 39° extensions — offering a mid-sweep wrist angle that balances aerodynamics with a natural forearm position for efforts of any distance.

• Sonic bracket offers an extensive fit range with minimal frontal area, keeping the cockpit clean and aerodynamic
• Ergo armrests aid rider comfort during sustained aero efforts, reducing pressure points
• A-Series 39° extensions allow fine-tuning of wrist angle independently of other fit adjustments
• Aero-shaped extension section maintains the same 87mm rise as previous alloy models
• New ergonomic end caps improve hand grip comfort in the TT position
• 22.2mm extension clamp diameter with 7.5mm offset, compatible with standard aerobar brackets

The 39° angle is the mid-point in the Sonic A-Series range — neither as flat as the 26° nor as upright as the 52°. It suits a broad range of riders, particularly those who find a very flat extension puts strain on their shoulders over long efforts, without wanting to adopt the more upright 52° position. The Sonic bracket itself is built around low weight and small frontal area, so it won't compromise your aerodynamics at the front of the bike.

Compatible with 31.8mm handlebars. Extension clamp diameter 22.2mm. Pairs with Profile Design Plus Series armrests for further adjustment options.