1. Made from anti acdi & anti-magnetic, 2. Suitable for using in Laboratories,micro-electronic, watches and cleanroom etc. The Tweezers are made from anti acdi & anti-magnetic, and suitable for using in Laboratories,micro-electronic,watches and cleanroom, etc.Size: AA-Sa: 125mm, 1-Sa: 115mm, 3-SA: 110mm, 7-SA:120mm