A lock is a device for raising and lowering boats between stretches of water of different levels on river and canal waterways. The distinguishing feature of a lock is a fixed chamber whose water level can be varied; whereas in a caisson lock, a boat lift, or on a canal inclined plane, it is the chamber itself (usually then called a caisson) that rises and falls.
Locks are used to make a river more easily navigable, or to allow a canal to take a reasonably direct line across country that is not level.
VERTICAL STANDARD| Size (Mtr.) | Wt.(Kg) |
| 1 | 6.20 |
| 2 | 11.70 |
| 2.5 | 14.40 |
| 3 | 17.20 |
LEDGER
| Size (Mtr.) | Wt.(Kg) |
| 1.2 | 5.55 |
| 1.8 | 6.95 |
| 2.4 | 8.95 |
TRANSOM| Size (Mtr.) | Wt.(Kg) |
| 0.8 | 5.90 |
| 1.2 | 9.70 |
| 1.8 | 13.10 |