Allen key B H3 A H1 C H3 C H3 H2 Step 1: Step 2: Attach chair back (A) with cushioned seat (B). Assemble legs(C) with seat frame(B). Using 4*bolts (H1) to lock up L/R back legs with Allen key (H3). Lock with 4*bolts(H2) by using Allen key(H3). Fasten in the center with 2*bolts (H2) by using Allen key (H3) as shown.