The supply electromagnetism arranges the timer, uses in the middle school physics teaching, the qual

The supply electromagnetism arranges the timer, uses in the middle school physicsteaching, the quality assurance.The product includes: The electromagnetism arranges the timer: Electric spark timer,sensitive galvanometer, digital timer, projection voltmeter, physical balanceand so on, this company products have attained the ISO9001 quality authentication,welcome to order0.02Schangeable with 0207

Electromagnetic Ticker Taper Timer