What is the arm length of the deep digging attachment?

The arm length of the deep digging attachment is specified as 20 feet, or 6.09 meters. This measurement is significant because it determines the reach and digging depth of the excavator, which is essential for deep excavation tasks. The design of hydraulic excavators includes precise specifications for attachments to ensure they operate effectively and safely.

In the case of deep digging projects, an adequate arm length allows the excavator to access deeper soil layers and perform tasks such as trenching or foundation work, which require a longer reach compared to standard digging attachments. The other options represent lengths that are shorter, which would be less effective for deep digging applications and could limit the excavator's functionality in scenarios requiring extensive depth. Therefore, the correct answer reflects the optimal arm length needed for specialized deep digging tasks.