Aluminium Coupler or Hose Joiner.Essential for special silicon hose building.three color can be select: silver, blue, red. luminium Coupler or Hose Joiner.Essential for special silicon hose building.three color can be select: silver, blue, red. bore length(mm) Weight(g) 16 100 65 19 100 75 25 100 95 32 100 125 35 100 150 51 100 200 60 100 230 63 100 245 70 100 270 76 100 295 aluminium joiner