Hot Spring Spa Moto-Massage Jet Assembly in Warm Gray. (73307) The warm gray colored Moto-Massage Jet is the current factory replacement for all Hot Spring. Also used on all 2005 to current spa models. Note: The included small silicone air tube is the only sub-part of the Moto-Massage jet that is available from the manufacturer. NOTE: This is the replacement for the White and Cool Gray Moto-Massage Jets. The White and Cool Gray are no longer available.