Everbilt 1/8 in. Barb x 1/4 in. MIP Brass Adapter Fitting 800049 - The Home Depot
Amazon.com: KOOTANS Forged Brass Reducing Hex Nipple, 1/4'' NPT Male x 1/8'' NPT Male Thread Adapter Brass Pipe Fitting Connector Couplings (Pack of 4) : Industrial & Scientific
Festo - AD-G1/8-1/8NPT-I - Thread Adapter, 1/8 ISO G male to 1/8 NPT female, zinc pl steel - RS
Adapter 7/16-28 (m) to 1/8” NPT (f) – LockNLube
Amazon.com: VCE 1/4" to 1/8" Adapter, 3.5mm 1/8 inch Male to 6.35mm 1/4 inch Female Audio Jack Gold Plated Adapter for Amplifiers, Guitar, Home Theater Devices, Laptop, Headphones - 8 inch : Electronics
Amazon.com: GlowShift 1/8 BSPT Male to 1/8-27 NPT Female Gauge Sensor Sender Thread Adapter Reducer : Automotive
1/8" to 1/4" Stereo Adapter - Etymotic
NANYI 1/4'' Male to 1/8'' Female Stereo Headphone Adapter Connect Cable, Upgrade 6.35mm Jack Stereo Socket Male to 3.5mm Jack Stereo Plug Female for Headphone, Amp Adapte, Black 1-Pack - Walmart.com