(4) ea Sweeney's S9014 Solar Powered Mole & Gopher Repellent Sonic Spikes Sweeney's Solar Powered mole and gopher repeller spikes offers a poison-free way to drive away moles, gophers and other underground rodents. Every 30 seconds, sonic pulses penetrate the soil, emitting a penetrating sound which is irritating to moles and gophers who are virtually blind and extremely sensitive to sound and vibrations. This method encourages moles to leave the property, and the solar operated spike continues to discourage return visits. No batteries are required to operate the waterproof solar spike; one solar charge will last up to 5 days. The spike is built with a mow-over design and safe to use around pets. Allow 7-14 days before ground rodents start to move away from the area.