Difference between Apex Mills DNB381 and DNB383?

[ULEWZ]

I have two competing offers for a quality impact screen, one lists a DNB381, and the other touts a DNB383. Does anybody know the difference as the Apex Mills website only lists Birdie, Eagle, and double Eagle with no mention of a P/N.
Thanks

[TripleBogeyPar]

I have an enclosure from bullseye golf with the apex mills DNB381 great screen vey quite and has a great picture