| 摘要 |
The trough for growing plants from seed is made from a sheet metal blank of rectangular form which is folded to form a trough of U-shaped cross-section. The end walls have folded in pleats at their corners. Both end walls and side walls have folded over edges of double thickness. The folded in pleats enable the side wall in the corner region to be folded outwards if required in order to allow excess water to be drained off if required. Alternatively, the end and side walls can be left vertical to retain water in the trough.
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