The RT-5SW long-range, dual-slope laser from Topcon retains features of the RT-5S series, including five-arc-second accuracy — less than 1/32 of an inch per 100 feet. An integrated radio remote controller handles two-way communication to 1,000 feet. Radio communications between the remote and the base laser allow the operator to verify adjustments from the machine's cab. The Smartline automatic guide-alignment system matches grade by automatically scanning to hit the alignment target. With the grade-matching function, the unit will then rotate the transmitter's grade mechanism to match the target's exact center. The unit's dustproof, waterproof housing contains an auto alignment feature that has a range of 450 feet.