Spring terminal blocks have various purpose. Pitch have 2.54/3.5/3.81/3.96/5.0/5.08/7.5/7.62/10.0mm are available. And majority of those items are all assembled slice by slice. Screwless terminal blocks is designed by the IEC60998, UL1059 and CSA C22.22 No.158 standards. Now, all of materials are with ROHS compliant.