Substrate fruiting bag
Unicorn 4A — Mushroom Substrate Fruiting Bag (Small)
★★★★★4.9
OysterShiitakeLion’s maneChestnutKing oyster
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The most versatile substrate bag in the Unicorn range. Works across the widest range of species — 0.5 micron A filter balances gas exchange without over-drying your block.
Choose pack size
✓ Based in the UK • in stock, ready to post
✓ Free Royal Mail Tracked delivery
✓ Made in USA by Unicorn Bags LLC since 1990
Filter
0.5µ A
Capacity
Up to 3kg
Size
19" × 8" × 5"
Material
3.0 mil PP
Find your bag
Which bag is right for you?
| Unicorn 4T | Unicorn 10T | Unicorn 14A | Unicorn XLSA | |
|---|---|---|---|---|
| Type | Grain spawn | Grain spawn | Substrate | Substrate |
| Capacity | Up to 1kg (2.2 lbs) | Up to 1.8kg (4 lbs) | Up to 3kg (6.6 lbs) | Up to 6.8kg (15 lbs) |
| Filter | T - 0.2 micron | T - 0.2 micron | A - 0.5 micron | A - 0.5 micron |
| Best for | Rye, wheat, millet & popcorn grains | Rye, wheat, millet & popcorn grains | Straw Pellets, Hardwood Pellets, Sawdust, Masters Mix, Soya Hulls & Wheat Bran | Straw Pellets, Hardwood Pellets, Sawdust, Masters Mix, Soya Hulls & Wheat Bran |
| Size | 4" × 3" × 18" 10 × 8 × 46 cm | 5" × 4" × 18" 13 × 10 × 46 cm | 19" × 8" × 5" 48 × 20 × 13 cm | 24" × 10" × 5" 61 × 25 × 13 cm |
All bags are 3.0 mil polypropylene — autoclave & pressure cooker safe at 121°C / 15 PSI