... with EN74/BS1139 :Type: Forged Single coupler Single coupler Scaffolding Single coupler Steel Single couplerSize: Single coupler Single Coupler ... as spigot support, deck retainer, toe board fixing, ladder bracket and so on. Double coupler 1.join two scaffolding tubes having ... assmbly systems of system scaffoldings .The vertical pole,the ledger,the corss braces,the tri-brackets,planks,and the base ...