Constructed from impact-resistant acrylic block, Series ACR measures water up to 400 mL/min or air up to 15 sL/min. They are available with Viton O-rings and stainless steel fittings or Buna-N rubber O-rings and brass fittings. Displaying both English and metric units, direct reading scales are mounted by locating holes between rear of acrylic block and backing plate, facilitating removal and mounting of additional scales for different fluids and flow rates.