Adjustable spreader end Our latest spreader end cap design is manufactured from tough composite and incorporates two wire slots to give a tight grip on either 2.5 or 3 mm wire. This enables spreader dihedral to be permanently locked into the spreader system. The spreader end comes complete with a vernier length adjuster which can be adjusted in 5 mm increments. Non-adjustable spreader end A simple fixed spreader end for masts that do not require any spreader length adjustment.