Hello all, I am working on writing my inspection essay for the Advanced Inspection of Crawlspaces course. Just took a picture of the bottom plate of my house and don’t know the proper name for these anchors. If it’s a lag bolt, it’s an odd looking one. Thank you in advance.
Looks like a drive-pin anchor or hammer-set anchor.
Welcome to the forum,Leif enjoy. 
Thank you, the head is deformed a little, like it was hammered in.
Thank you for the welcome! I’ve been reading and learning a ton.
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It’s an anchor bolt.
Typically into concrete it’s either a j-bolt (set into poured concrete) or wedge bolt (driven into cured concrete).
A little hard to identify the type when all you can see is the nut & washer 
Thank you. Best I can tell after y’alls responses is that it’s one that’s driven in. Up close it doesn’t appear to be a nut, but it is hex.
Looks like what is known by the brand name Hilti or Hilti Fastener, but there are also other brands. They are driven with a ‘powder actuated tool’. in other words, driven with a .22 cal blank cartridge.
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It’s not an anchor bolt, it’s a steel pin, shot into place using a powder-actuated tool typically made by Ramset or Hilti. They use a .22 caliber cartridge and pins are available from about 1-inch to about 3". Some pins come with washers attached, with other systems washers are placed first and then the pin shot through the washer. (https://www.youtube.com/watch?v=2fXgLsHsZNI&t=242s)
Very common in fastening down home interior walls in slab-on-grade construction.
They lack the uplift resistance of anchor bolts (by a long shot) and are typically not used on exterior walls as primary anchors.
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Great info, thank you!
Still more evidence that my house is cheaply built 
(it’s an exterior wall)
Looks like a Ramset.