This is a 100-Pack of our Atlas Professional Green Screw-On Mixing Nozzles for the New 3M 1:1 and 2:1 ratio 50ml Duo-Pack Cartridge Design (also called a B-System design with a large gray screw-off cap). These are the longer 4.5-inch 24-element mixing nozzles, which are preferred for most Urethane and many Epoxy adhesives that require more mixing elements to properly mix. They are also in the high-efficiency quadro style, which reduces wasted material by about 50% vs traditional helix nozzles. They reduce wasted adhesives through smaller cavities and more efficient interior mixing elements, and with a guaranteed-correct A-B alignment when mixing the two parts which eliminates incorrect mixing ratios. Works perfectly with the new 3M EPX Duo-Pak Cartridge Design, as well as with all B-System and S-System 50ml "Square-Back or Rectangle-Back" Cartridges. Essentially, its for all cartridges that have a large gray twist-off cap on their outle (instead of a smaller white cap). 1) Syringe Inner Diameter: 6mm/ 0.25"; Tip-end hole Inner Diameter: 0.5mm/ 0.06" 2) Inner Mixing Elements: 24 elements (how many mixing points are found inside the nozzle) 3) Total Syringe Length: 115mm/ 4.5") Package Contents vary by the Pack size you select. 4) Fully compatible with the 3M EPX Green Mixing Nozzle Stock Number 62-9154-9148-4 (UPC 0-76308-86434-7) 5) As well as the Bulk 3M Stock Number 62-9171-9954-9 (UPC 0-63806-01003-1)