The OmniFilter K2 Undersink Filter Installation Kit can be used with OmniFilter models OB1, OB5 and R14. The Omni K2 is an installation kit to use with filter cartridge housings that have 3/4 inlet/outlet and use 3/8 copper tubing. Use the Under Sink Water Filter Installation Kit for easy installation of OMNIBASIC and OMNIREGULAR water filters. The Omni K-2 Kit includes mounting bracket plastic tubing and installation hardware. This Sink Kit will fit standard 3/8 (O.D.) copper water line only. Other size or type water lines require different unions. The OmniSink Kit comes with complete installation instructions including diagrams