Seaflow Blue Silicone Hose Reducer (45mm - 38mm ID)
Oil Resistant Straight Rubber Hose Reducer (22mm to 19mm) for Provent Pro Vent | eBay
Brass Pipe Fittings, Water Hose Adapter, G 1/2 Female to G 3/8 Male Reducer Adapter, Compression Fitting for Kitchen Bathroom Faucet, Pipe Connector with Rubber Washer,(2 Pack) : Amazon.co.uk: DIY & Tools
OHOB-COOL 3 to 3.5 Inch Silicone Reducer Coupler Hose,Length 3",ID 3″ to 3.5 (76-89mm),4-Ply Reinforced Turbo/Intercooler/Intake Piping
Blue Silicone Reducer Hose/Reducer Silicone Rubber Hose for Car - China Straight Reducer, Reducer Silicone Hose | Made-in-China.com
Flexible Rubber Pipe Reducer
Straight Oil Resistant Rubber Hose Reducer (25-16mm) for Provent Kits