The 10-pin line seen here likely was the most recent as Ma Bell and a lot of independent phone companies in the New England vicinity were replacing aging poles that had six-pin crossarms when this photo was taken. The latter had two lag screws affixing them to their poles, often with crossarm braces. These older poles date back to the 1880s and 1890s. The 10-pn crossarms had a center bolt method of attachment, two crossarm braces mounted on the outsides of their arms and obviously provided the capacity for more subscriber circuits as well.