As mentioned above, you are more likely to get pallets for free from a smaller location that generates pallets in small quantities, or if the pallet sizes are not attractive for resale to other pallet users. Non-standard pallets are more likely to be single-use pallets. Single-use or expendable pallets will likely have bright new wood instead of weathered material associated with pallets that have been used many times. On the other hand, single-use pallets are often made of lower quality lumber, so there are trade-offs involved. Low-quality pallets sometimes are manufactured with fewer nails, or shorter ones which can be more readily removed when taking the pallet apart.
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