A local greenhouse guy mentioned he used to grow a variety called Maine Pack, or Pac, Paq? that was a good tasting early tomato for around here but the flaw was the shoulders would crack and get even worse during rainy times.
I tried searching but found nothing on that variety.

The Dave's Garden website lists a variety called "Mainpak" and describes it as a 1975 Joseph Harris hybrid version of "Ace." No reviews.

Another website (cucurbit.info) says "Mainpak – Breeder and vendor: Joseph Harris Co. Characteristics: F1 hybrid, large fruit, semi-determinate growth habit; main season. Resistance: none claimed. Similar: Ace. Adaptation: northeastern United States. 1975."

Another says "Round red fruit. Plant 120 to 160 centimeters high. 70 to 75 days. Indeterminate growth. Variety from USA introduced in 1975. Looks like 'Ace'."

That could be it.
I assumed the name was 2 words.
Thanks

They don't make that one easy.

plant does not set seed, flowers are sterile, or plants will not come true from seed

slugworth wrote: ↑Thu Jun 03, 2021 6:32 pm They don't make that one easy.

plant does not set seed, flowers are sterile, or plants will not come true from seed

I believe that's what they say for all F1 hybrids on Dave's Garden. In this case, you can fairly assume that it'll be fertile, but not true to type.

Someone needs to make a tomato database for hybrids!

I talked to the guy today.
He did buy the seed back when from Harris
He stopped growing it in 1980