The Northwave Sonic S.R.S. Shoes are a well-designed mid-level cycling shoe. As with all of Northwave's shoes, they have been developed using Bio-Mapping so that they are properly designed to fit the shape of your feet while pedaling.
The uppers of the Sonic S.R. S. shoes are a multi-layer Thermowelded construction with Northwave's Airflow System. The Thermoweld consists of a light microfiber Polyurethane that has been coupled with large mesh vent inserts -- the total thickness of the upper is the same as a traditional single-layer construction. Working in conjunction with this design is a series of vents that channel air into the sole to keep your feet from overheating. The soles are NRG Air, Carbon reinforced which are stiff and won't break your wallet like a full carbon fiber sole. They are compatible with any 3-hole SPD pedal.
To ensure that your feet are held in place and that the shoes don't chafe or slip, Northwave used an integrated Heel system. By placing it inside of the shoe, the need for external parts is eliminated. This reduces weight. A Performance Advanced footbed is used. This footbed features optimal arch support to keep your feet in ideal pedaling position. The shoes are secured with two hook and loop straps and Northwave's S.R.S (Slim Ratchet System). This aluminum buckle micro-adjusts so that your shoes always fit perfectly -- even if they need adjusting on the fly.
The Northwave Sonic S.R.S. shoes weigh 283 grams. They are available in whole and half sizes from 39.0 to 45.5 and in whole sizes 47.0 and 48.0. They come in four colors: White/fluo green, Black/white, White/red, and Fluo yello/black.