Firmer gouges are strong tools designed to be used hard with a hammer or mallet for bringing wood rapidly to approximate shape. Unlike lighter carving gouges firmers typically only deal with initial waste removal, so you don't need different sweeps but it is useful to have a choice of widths. 
The curved blades take nice deep bites, working across or diagonal to the grain they cut the fibres rather than splitting them; with a nice sharp edge and steady blows it's surprising how quickly you can make progress. A common practice is to drill some holes first to establish the positions of transitions or boundaries, then chommel away until you reach them.
The hooped beech handles are very sturdy and will stand up to a hammer or mallet for years while that lovely Narex isothermally hardened steel takes and holds its edges beautifully.
The set of 6 gouges include: 8, 10, 12, 16, 20 & 26mm - #7 sweep. 
Supplied in a stained beech presentation box
Approximate Measurements:
| Size | Overall Length | Handle Length | Usable Blade Length | 
| 8mm (⁵⁄₁₆") | 260mm (10¼") | 135mm (5¼") | 95mm (3¾") | 
| 10mm (⅜") | 265mm (10½") | 135mm (5¼") | 95mm (3¾") | 
| 12mm (½") | 265mm (10½") | 135mm (5¼") | 95mm (3¾") | 
| 16mm (⅝") | 270mm (10⅝") | 135mm (5¼") | 95mm (3¾") | 
| 20mm (¾") | 277mm (10⅞") | 135mm (5¼") | 95mm (3¾") | 
| 26mm (1") | 277mm (10⅞") | 135mm (5¼") | 95mm (3¾") | 
 
         
                     
                     
                     
                     
                     
                     
                     
                     
                     
                     
                     
                     
                     
                     
                     
                     
             
             
             
            