Named for its shape, the B square is a tool for 'feeling' square as much as seeing it, particularly in situations where you are eyeballing for square in two axis at once. The bows allow it to be held comfortably in a variety of positions and also brace the working faces giving it an inherently rigid form.

The square is intended to augment the user's sensory accuracy for the final cuts of a chiselling operation that produce the mating surfaces of joints, after the bulk of the waste has been removed. For example paring the shoulders of a tenon to the gauge line, or trimming the ends of a mortice plumb. You can also use it with a fine saw for the first few strokes that establish a nice vertical kerf, or just use it as a square to check your work.

• Approximate dimensions: 53 x 33 x 15mm
• Internal diameter: 19.5mm
• Tolerance: +/- 0.0007" (total deviation)
• Powder coated cast Steel
• Made in Birmingham, England