Amazon.com: In Line Radiator Hose Filler Neck Cap, Radiator Coolant Filler, Radiator Cap with T Branch Water Pipe Kit, 38mm 1‑1/2in OD with Temp Display Cap T6061 Aluminum Polished Surface : Automotive
In-Line Radiator Filler Neck 38mm
19mm Aluminum Radiator Filler Neck Cap Charge Cooler Header Overflow Tank 3/4" | eBay
Aeroflow In-Line Radiator Filter / Filler, Black | Pegasus Auto Racing Supplies
Inline radiator cap - what cars| Grassroots Motorsports forum
1-1/2" Billet Aluminum In Line Radiator Cap Hose Filler Neck 38mm
Amazon.com: ZM Aluminum Upper Inline Radiator Hose Filler Adapter Water Neck 1.5" to 1.5" : Automotive