The features of the Haenel model 1900 were protected by one DRPatent and three DRGMs, registered and protected for 6 years designs.
DRPatent Nr.120862 from April 28, 1900 for the double stack magazine, it’s follower leverwork and the floorplate mounted latch locking into the triggerguard,
DRGM 135556 for the separate gas shield, obviously missing here.
DRGM 135992 for the two-part firing pin. The bolt body contains a tipless striker, while a separate firing pin is mounted inside the bolthead.
DRGM 206216 for the two part bolt stop and ejector housing. The forward housing contains an ejector lever, while a spring and plunger for the ejector is inside the rear bolt stop.

Gas shield, bolthead and ejector housing were all marked “DRGM”. On this rifle you may see the dovetailed slot for the ejector housing, but the housing is missing. As Lyman made #36 receiver sight bases for the M88 action, but not for the Haenel M1900, someone in the USA adapted such an available sight to the Haenel. The Lyman base = bolt stop replacement does not contain the M1900 ejector spring and plunger, so the gunsmith had to design a different solution for the ejector.

“248” is the old gauge number, in use until 1912, for a “7 mm” bore.
The bolt is not original to the rifle. There are no CROWN-crown/N civilian proofmarks on the underside of the handle, complying to the civilian proof service load information. And it is not marked with Haenel’s “star over H” mark, but with the “Crown over SS” factory mark of V.C.Schilling, Suhl. So it is a military M88 carbine bolt. As these are near identical, except for the protected details noted above, to the M1900 bolt, it is easily adaptable to a Haenel M1900, with a bit of file work on bolthead and maybe cocking piece. At least, the M88 type ejector "finger" of the Lyman #36 rear sight base works with a M88 bolt head, but not with a Haenel M1900 one.