Inverted Oil Bottle Drain-Down Coupler
This tapered double-cone coupler stacks an upside-down quart bottle of oil, coolant or ATF on top of another bottle so the last drops drain from one into the other. The top seat takes bottle necks from about 26 to 50 mm. The 18–30 mm ribbed spigot wedges into necks with an inner diameter of about 19–30 mm. Four ribs inside the seat and three outside the spigot leave air paths so neither bottle seals and glugs. The part is 86 mm tall with a 68 mm drip-lip flange and prints mouth-down without supports.
garage automotive oil-bottle funnel
⚠ Flagged: automotive electrical. Not for safety-critical use without independent engineering review.