'typical' railroad track hardware

A few weeks ago I showed a few similar items that are unique in my 'choo-choo track hardware collection' simply because they're new and unused examples of a couple spikes and a rail anchor clamp.

https://www.collectorsweekly.com/stories/306368-two-railroad-track-spikes-and-an-anchor

Here's a few much more typical such things, as commonly and easily picked up anywhere nearby most any actual railroad track, and in their officially "used" condition. These are one track spike and a rail anchor like those in my other showing, except the anchor here is of a differently shaped design.

The large round headed bolt is used with things called junction plates (I think) where two lengths of rail are fastened together, I have a couple large square nuts around here someplace (but not handy for the pics) that theoretically would thread onto it. Notice the shape of the 'shoulders' inside its head, so it would fit and lock itself into an elongated hole in the junction plate.

I'm not certain what the large square/washer headed lag screws are used for specifically, but would believe they'd be used to secure other sorts of equipment to railroad ties for purposes beyond actually holding the track itself down and in place -- all those other assorted machines and boxes and poles and fun things that are otherwise necessary to keep the trains running.

Only the bolt and lag screw have any markings, consisting of a few letters/characters on their heads that probably either indicates their "grade" (read: strength rating) or manufacturer. Pic 4 here tries to show that, despite the rust.