I just bought the one from Harbor Freight and amazingly it is actually nicer than the Sperry that I got from Home Depot for three times the price (the HF unit is only 12.99 with 25% off coupon), Plus the HF unit is easier to use, has a headphone jack (nice for when using in noisy environments) and it's also got a much better speaker plus it comes with a storage case. This little gem will pay for itself the first time that I use it. Every home owner should have one of these in their toolbox. This will also be a time saver when tracing wires in a car