Product Name: SS 316 Concentric Reducer
Type: Concentric Reducer
Design Standard: GOST 17378
Material: Stainless Steel SS 316
Size & Wall Thickness: 57 mm * 4.0 mm to 25 mm * 3.0 mm
Source: https://www.landeepipefitting.com/stainless-steel-316-concentric-reducer-gost-17378-57-25-mm.html