The 30-degree down elbow is a 220-mm angled lead off with an external lid, so that new optical fibre cords can be installed within the elbow and existing optical fibre cords removed, where necessary. This is usually used where an angular duct feed off or an alignment adjustment is needed. There are two 220-mm outlets. One is equipped with a glued-in, modified joiner. (The special joiner provides a smooth internal curve for optical fibre cords). The other side uses either: a standard joiner (Part No. TC1279-25) or a slotless joiner (Part No: TC1279-250A); that are available separately.