Additional arm joint that allows for replacement or additions to your current mount for the ELFW-07, ELPT-07, ELSJ-07, ELDJ-07, EL30-FW, EL30-03, EL31-03, EL32-03, LM30LP, LM30T, LM30SJ, LM30DJ, LM37LP, LM37SJ, LM37DJ, DC30LP, DC30T, DC30SJ, DC30DJ, DC37LP, DC37SJ, DC37DJ, EU30LP, EU30T, EU30SJ, EU30DJ, EU37LP, EU37SJ, EU37DJ (in Black).