Maint | cylchedd y frest (cm) | Cylchedd gwddf (cm) | Hyd cefn (cm) |
8 modfedd | 25-30cm | 18-22cm | 20-23cm |
10 modfedd | 28-33cm | 22-26cm | 25-30cm |
12 modfedd | 33-38cm | 26-30cm | 30-35cm |
14 modfedd | 38-40cm | 30-35cm | 35-40cm |
16 modfedd | 40-46cm | 32-38cm | 40-45cm |
20 modfedd | 44-52cm | 36-44cm | 50-55cm |
24 modfedd | 50-66cm | 42-52cm | 60-65cm |
28 modfedd | 64-80cm | 50-62cm | 70-80cm |