Denon DL-110 and DL-160, the latter sadly discontinued. These cartridges for phonograph turntables work according to the moving coil principle, which is much more seldom (and more expensive) than the standard 'moving magnet' (see same article as linked herein before) principle. Each cartrige has a thin metal bar of ca. 1-2 mm (estimated) thickness and with a length of maybe 6 mm, at the end of which towards the photographer there is the diamond which 'reads' the information stored on the phonograph record. This diamond can be seen in the image as the very (extremely) tiny thing (protrusion) pointing downwards located in the middle of the transparent, U-shaped structure on the lower side of each of the cartridges - the diamond being mounted at the front end of the tiny metal bar.

PS: If you read the above and think "But the needle is covered by the transparent structure, how should it be able to be in contact with the record?" - the solution to this question is that once the cartridge is in use in a turntable, the transparent thing is turned upwards by 90 degrees by the user, as it is only a protection for the needle when the latter is not in the place where it should be. This is the case, for example, on the way from the factory to the user's/buyer's home. Hence, the shown items are in the "protection in place" state. In the image directly below, a cartridge of the red type above is mounted in a turntable and is shown in use during playback of a record - while the transparent protective structure is tilted upwards by c. 90 degrees towards the photographer, as described further above.

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  The red cartridge above in use in a turntable, needle protection tilted upwards to enable mechanical contact between needle and record surface