30,000+ Happy Customers
The Sac O2 Microbox rectangle container is designed for efficient mushroom cultivation. It incorporates a depth-filtration system for clean airflow and contaminant blockage, optimising your fungal growth environment. Select from various filter types to match your cultivation needs, ensuring healthy development and yield.
- Cover: 180 × 120 mm
- Base: 172 × 110 mm
- Height: 92 mm
- Volume: 1600 ml
Full box sizes: Bulk (153-175/Box)
- Gamma Irradiated (G): 153 lids/153 vessels
- Non Gamma Irradiated, Autoclavable (NG/NP): 165 lids/165 vessels
How Do Stock Availability and Lead Times Work?
We stock a selection of our most popular mushroom strains for immediate dispatch, while others are produced to order and may require a longer lead time before shipping.
The graphic below explains our ordering and delivery process, making it easy to see what to expect when placing an order.
Click here to view the graphic.
Our lead times vary depending on the product and current stock levels. Please note, these are approximate times and can vary depending on specific circumstances. Bank holidays may affect lead times. For any urgent requirements, please contact us via out chatbot.
By default, if your order includes multiple items with varying lead times, the entire order will be dispatched according to the longest lead time. This ensures your products arrive together in one shipment.
Lead times can be found on every wholesale spawn product page.
Delivery & Returns
Delivery
Note: Please refer to the specific lead times shown on product pages for more accurate delivery times.
- Small Orders (E.g. 100ml Spawn, Plugs): Sent via Royal Mail large letters.
- Medium-Sized Orders (under 2kg): Royal Mail 24-48 hour tracked parcel.
- Large Orders (2kg+): via DPD Express or APC.
This does not apply to our Gift E-Cards, which are delivered via email.
If you'd like your parcel left in a safe place, this needs to be arranged directly through the courier's website or delivery notification.
To enable this function you must leave a valid email address. Once your order is on its way, you should receive a notification from the courier with a link to manage your delivery. Simply follow that link to choose a safe place or make any other delivery preferences.
Unfortunately, we’re unable to set a safe place on your behalf.
Extended Delivery Areas
Certain UK postcodes may require 2–5 business days for delivery.
While we are able to ship to these locations, we cannot accept responsibility for the condition of products upon arrival due to the extended transit time. By placing an order with a delivery timeframe of 2–5 business days, the customer acknowledges and accepts this risk.
If your postcode falls within an extended delivery area, you will be notified at checkout before completing your order.
Returns
Due to the perishable nature of spawn we are unable to accept cancellations of orders or returns of product.
- If your mushroom spawn arrives damaged, defective, or not as described, please contact us at hello@urban-farm-it.com within 24 hours of receiving the item. You will be eligible for a replacement or refund if we are notified within this timeframe, along with supporting documentation such as photos of the item and packaging.
- Refunds or replacements will not be issued for reports received beyond the 24-hour window, as the quality of perishable items can degrade rapidly.
See our returns policy here.
Choosing The Right Container
Choosing between a mushroom growing bag and a MicroBox depends on your goals, growing experience and the mushroom species you are cultivating. Click the button below to view our easy-to-follow guide.
Why choose this product?
Premium quality
Crafted with the finest materials for lasting durability
Commercial-Grade Performance
Trusted by professional mushroom farms across Europe for reliable, consistent results.
From Hobby to Commercial Scale
Suitable for first-time growers, small-scale producers and commercial mushroom farms alike.
Optimised Gas Exchange
Species-matched filter options provide the right balance of fresh air and contamination protection.
FAQs
Should I Use a Mushroom Growing Bag or a MicroBox?
Choose a Mushroom Growing Bag if:
- You want larger harvests and higher yields.
- You are growing multiple blocks at once.
- You want to use the same cultivation methods as commercial mushroom farms.
- You are growing species such as Oyster, Lion's Mane, Shiitake or Reishi on bulk substrate.
- You need a cost-effective option for larger-scale production.
Our SacO2 Fruiting Bags are designed specifically for mushroom cultivation and are available with filter options matched to different species.
Choose a MicroBox if:
- You are new to mushroom cultivation.
- You want a reusable growing container.
- You are running experiments or testing new substrates.
- You prefer a rigid container that is easy to handle and clean.
- You are growing small batches or learning sterile technique.
MicroBoxes are autoclavable, reusable and available with different filter options to suit a range of mushroom species.
For more in-depth information, click here to view our helpful guide.
What is the difference between a G Filter and a T Filter mushroom bag?
The filter controls how much air can pass through the bag during colonisation and fruiting.
- G Filter Bags provide higher gas exchange and are ideal for fast-growing species such as Oyster mushrooms.
- T Filter Bags provide greater contamination protection and are recommended for slower-growing species such as Shiitake, Reishi and other long-incubation varieties.
Which filter should I choose for a MicroBox?
MicroBoxes are available with three filter options:
- #10 White Filter: Lowest gas exchange and longest incubation times.
- #30 Red Filter: Medium gas exchange and balanced performance.
- #40 Green Filter: Highest gas exchange and fastest colonisation.
What are mushroom spawn bags used for?
Spawn bags are used to grow mushroom mycelium on sterilised grain before transferring it to a fruiting substrate. Our SacO2 Spawn Bags feature a zipper seal for easy inoculation, full-length filter strips for even gas exchange and a V-gusset base that forms a stable block during colonisation.
Are MicroBoxes reusable?
Yes. Unlike cultivation bags, MicroBoxes are rigid, reusable containers that can be cleaned, sterilised and used repeatedly. This makes them a cost-effective and environmentally friendly option for mushroom cultivation.