The AdirPro Prism Pole Extension is highly durable with its aluminum constructions that is sturdy, lightweight and wear resistant which makes usable for long duration. There are male and female 5/8 x 11 threads on either end for accessories and attachment to lengthen poles. This antenna extension poles has 1 foot pole extension (30 cm) length and 1 inch outside diameter. The AdirPro Aluminum Prism Pole Extensions come in 1' and 4' lengths, and also has different colors. You can choose from fluorescent yellow, standard yellow, or red finish.