Main Type 20

This cutout type is a combination of the cutout types 10 and 15, that means, it has got a lug on both sides, cf. the figure below.

Figure 2:27. Main type 20, radii and clearances.

All normal profile types are supported (not U-bars).

R2, R5 and R8 are irrelevant.

C2 is normally irrelevant except for T-bars and C6 is irrelevant for flat bars.