B1 and B2
The B1 on the B-scale requires moves that are at a skill level of 5.12 or 5.13 on the Yosemite Decimal Scale (YDS) which is the scale used for rating the hardest moves required on a rock climb. The B2 on the B-scale according to "Mountaineering: The Freedom of the Hills" constitutes moves as hard as 5.15. This is as hard as it gets.
B3
A B3 bouldering climb is a successful B2 climb that has not been repeated. If it is done more than once, the rating goes back to B12.
V0- to V6
The B-scale has ratings that float somewhat but the V-scale gives precise ratings that are comparable to the YDS. V0- is equal to a 5.8 on the YDS, a V0 is equal to a 5.9, V0+ is equal to a 5.10a/b, V1 is equal to a 5.10c/d, V2 is equal to a 5.11a/b, V4 is equal to a 5.12-, V5 is equal to a 5.12 and a V6 is equal to a 5.12+.
V7 to V15
The Sherman V-scale continues to include V7 which is equal to a 5.13-, V8 which is equal to a 5.13, V9 is equal to 5.13+, V10 is equal to a 5.14-, V11 is equal to a 5.14, V12 is equal to a 5.14+, V13 is equal to a 5.15-, V14 is equal to a 5.15 and a V15 is equal to 5.15+.
