1240F2314 - Steel Modular Core Diffuser with Square Neck - 14" F23 Lay-InKrueger 1240 F2314 Steel Modular Core Diffuser with Square Neck 14" F23 Lay In The Krueger 1240 series modular core diffusers are one of Kruegers most quiet and versatile diffusers, combining excellent performance with on the job flexibility. The 1240 series diffusers exhibit typical isothermal throws of 20 to 30 for 4 way air distribution and 40 to 60 for 1 way air distribution. The modular cores in the neck maintain a tight horizontal air pattern at