A recessed head
cylinder will require both feeler gauges and depth micrometer.
Once room temperatures reach 57C, the cover plate melts off and the recessed head will drop down to its operating position.
The system sees water run directly from the mains and the sprinklers have recessed heads for a better appearance.
In order to make up for this and keep volume standard at 225 liters, chateau barrels have a recessed head, and the croze (or circular groove where the barrelhead sits) is farther inside, making it possible to see more of the toasted staves when the barrel is closed.
A thin-stave barrel with a recessed head and crossbar is called chateau ferre if it is made without the chestnut hoops and vime.
We also didn't like the fact you have to dig the crushed garlic out of the recessed head
In addition to the standard slotted head for conventional screwdrivers, other recessed heads
are designed for use with special screwdrivers, bits or keys.