This is direct from B3 website, this has also been discussed in much detail before on here.
GRADING/PRICING
Here at B3 Cricket we only make our bats out of the very finest English willow.
Because we don’t “mass manufacture” we are able to invest the time to understand the needs of each and every customer to help them select their ideal piece of willow to suit their style of play and budget.
Upon arrival at our Nottingham factory we weigh and check the density of each cleft (uncut piece of willow). We then use our expertise to grade each cleft into a One, Two or Three stripe.
Please remember that we are always happy to discuss the grain structure, heart (redwood) / lightwood preference, shape and balance with you to help you get your perfect B3 bat.
Below we explain what you can expect from a One, Two or Three stripe bat:
3 Stripes
This is the finest Grade 1 English willow that money can buy. Each cleft will have between 6 and 20 straight grains and only minor blemishes outside of the main playing area.
The weight, balance and density will be conducive to providing a bat that picks up lighter than it looks.
2 Stripes
High quality English willow with between 5 and 12 grains and may contain some light butterfly stain and there may also be pin knots but this will not affect the performance of your bat.
1 Stripe
Our 1 Stripe represents outstanding value for money as our entry level grade. The grain may not be straight in every case and will usually contain some pin knots which are all completely natural and only affect the bats appearance.