4mm 1 x 19 plastic coated wire, 6mm approx finished diameter. It is almost impossible to Talurit splice this wire neatly and safely - it needs either rollswage terminations or swageless ends. The standard guardrail configuration is for a fork terminal at the front going straight on to the loop on the pulpit with either a guardrail eye or a guardrail perlican at the back - both these terminations have ends which can be unscrewed, leaving just the stud to pass through the stanchions. That allows guardrails to be replaced without removing stanchions. If using a lanyard on the guardrail eye for tensioning we suggest you allow 150-200mm.