Hi
@marble,
The only compatibility of the chainring you need is:
- Proper Bolt Circle Diameter (BCD). I am almost ready to bet it is 104 mm BCD in your Explore+
- Number of teeth (it will be 42T in your case I think)
- Number of bolt holes (I am almost sure it is 4 holes for your Explore+)
The definition of BCD.
You do not necessarily need a steel chainring. Modern chainrings (except some for MTB) are typically aluminium alloy, and they last far longer than the cassette cogs (as the strain of the chain on the chainring spreads over big number of teeth).
Now, you wrote somewhere that the replacement chainrings seemed too fancy. It is all good. Modern chainrings come with special tooth arrangement such as Narrow-Wide or WAVE. The tooth arrangement is meant for your chain not to drop from the ring.
Unfortunately, Giant wrote nothing about your specific chainring. I looked at a stock photo of a 2019. Is the plastic chainguard bolted directly to the chainring? If you look carefully at the back of the chainring, can you see the bolt nuts? If not, your chainring
might be a 104 BCD, 4 bolt, 42T chainring from Praxis. (Praxis is using threaded chainring bolts for convenience; all other use MTB bolts with nuts).
If you look for a good chainring of the parameters matching your old one, look to offerings from Praxis or perhaps Garbaruk.
P.S. Why not just ask your Giant LBS? The trouble with any replacement chainring is it might not accommodate your existing chainguard. FWIW, I do not use the chainguard after having replaced the chainring to another make.