Our Stainless T-Slot Roll-In T-Nut is designed for 15 Series (1.5") aluminum extrusions profiles, featuring a 5/16-18 thread and a spring-loaded ball to hold it in place during vertical assembly. It is a stainless steel alternative to the standard zinc-plated steel. The roll-in T-nut with ball spring is often the "unsung hero" of assembly because it solves two of the most frustrating problems in hardware: gravity and closed-off frame ends. The ball spring prevents the nut from sliding down, making vertical,, or complex assemblies much easier. These roll-in nuts can be inserted directly into the slot at any point, removing the need to access the end of the profile. Made from 304 stainless steel, offering superior corrosion resistance for both indoor and outdoor environments. Designed specifically for 15 Series (1.5" or 8mm slot) T-slotted aluminum extrusions.  Provides a secure, reliable fastening solution for industrial, robotics, and framing projects.
 
Product Overview and Compatibility
 
80/20 Compatibility: This product is specifically designed as a stainless steel equivalent to 80/20 Part #13021 (often referenced interchangeably with similar roll-in styles like #13040).
Material: Constructed from 304 Stainless Steel, providing superior corrosion resistance compared to standard zinc-plated steel options, making it ideal for outdoor or marine applications.
Roll-In Design: Features a "roll-in" or "drop-in" capability, allowing the nut to be inserted into the T-slot from the side of the profile. This is crucial for adding hardware to frames where the ends are already blocked or inaccessible.
Ball Spring Mechanism: Includes a spring-loaded ball that provides tension against the profile, holding the nut in place even when the extrusion is positioned vertically. 
Installation: The "roll-in" design allows it to be inserted from either the profile end or the side, which is critical when the ends of the extrusion are already closed or inaccessible.
Self-Aligning: Features a ball spring mechanism that holds the nut in place within the T-slot, preventing it from sliding down in vertical applications and simplifying assembly.
 
Here is a breakdown of why these are generally preferred over standard slide-in nuts:
 
 
Retrofitting Capability: Unlike "slide-in" nuts that must be inserted before the frame is closed, these can be popped into the slot at any point along the rail.
Gravity Resistance: The spring-loaded ball bearing creates just enough friction against the back of the T-slot to keep the nut from sliding down vertical extrusions.
Self-Alignment: As you tighten the bolt, the "roll-in" shape allows the nut to rotate into its locking position automatically, ensuring a secure grip on the profile's inner lips. 
 
Specifications / Dimensions:
Thread Size: 5/16-18.
Length: 22.00 mm (approx. 0.866 inches).
Width: 13.5 mm - 13.7 mm.
Height: 7.00 mm - 7.2 mm.
Slot Fit: Designed for 15 Series (1.5") and 40 Series (40 mm) extrusions with an 8 mm slot.
 
 
Pro Tip 1: Always verify your extrusion's slot width before purchasing. While these fit many 40-series metric and 15-series fractional profiles, some specialized "Lite" or "Ultra-Lite" extrusions may have different internal dimensions.
 
Pro Tip 2: When using these on vertical profiles, "roll" them in with the ball spring facing the back of the groove. If the nut feels too loose or too tight, check if your profile is "Light" or "Heavy" duty, as the internal slot depth can vary slightly between manufacturers.