which allows for hand support during rapid twisting without losing control

Safety Classification: EN ISO 20347:2022 O2 FO SR (stated by manufacturer)

and nominal voltage (9 V) are details directly from the manufacturer's product text

See the manufacturer's product information for reference: Bahco product page

TX40 x 130 mm

Barrel for bent XT TIPS WXP120 Unit(s):Pcs which allows for hand supportSpare Parts Weller barrel for bent XT tips This spare part barrel from Weller is specified as a barrel for bent XT tips and is indicated for use with the Weller WXP120 soldering iron. The product is listed on Weller's official product page as a spare part with item number T0058765766N. Description T0058765766N is a replacement barrel designed to enable the use of bent XT tips with the WXP120. Information from the manufacturer's product page indicates