Yup clutch drive with the rounded butterfly ends. Holley carburetors used them on their metering blocks back when pterodactyls flew.
WiHa makes tools for these drives and unlike commercial garbage the WiHa tips lasts and lasts even when power driven. Look for molybdenum as an alloy agent. 99% of the neanderthal grade tools have chromium and vanadium but not molybdenum. Ever hear of "Chrome Moly" steel?
With a new hole in wood I use silicone grease on the fastener threads. Nope, it doesn't not make it easier for the screw to loosen but it sure makes driving them easier. Silicone grease does not harm wood.
