An exterior bottom end of the sleeve (146) has a castellated surface.

An interior bottom end of the tube (144) has a matching castellated surface.

The filter cartridge and its holder each have a keyed surface, one being a protruding 'key' and one being a recessed 'lock'.

The mill consists of several parts, including a notched surface where you put the chainsaw blade and adjust the depth and angle.

A conveyance surface (37) is a planar surface.

An exterior bottom end of the sleeve (146) has a castellated surface.

An interior bottom end of the tube (144) has a matching castellated surface.

A V-ribbed belt that includes a ribbed surface covered with fabric is provided.

In particular, the back (15a) of the toothed belt (8) is delimited by an undulated surface (15).

An engagement claw of the buckle is engaged with a serrated engagement groove formed on the outer surface of the band.

The first timing belt (106) has a belt surface and the rollers (114) have a rolling surface, such that the belt surface and the rolling surface are substantially coplanar with respect to one another.

The V- ribbed belt comprises an outer back-side surface, an inner front-side surface, and a load-carrying section disposed between the front-side and back-side surfaces.

A timing belt autotensioner (21) includes a mechanism actuated by the reversal of timing belt movement direction.

On the toothed belt (7) there is a coupling device for the automatic releasable connection of the toothed belt (7) to the bearing pallet (2).

The filter cartridge and its holder each have a keyed surface, one being a protruding 'key' and one being a recessed 'lock'.