I could not find a thread about posting pictures of mystery components and asking for help identifying them, so I thought I should start one so people can ask away without having to create a new topic each time.
I will kick the thread off with this one.
Must be a diode, probably silicon judging from the voltage drop, but could not find a datasheet or any info. The only mark it has is an “H”. Could I treat this as an 1N4148 or is there something special about it?