Our take on the RRD18 winding check

The 0.5 mm step is what makes the difference when you close a build: with 17 inner diameters between 8 and 16 mm, you land straight on the blank instead of taking up the gap with thread. The anodised aluminium and the 7 colours let you match the finish to the reel seat, for less than a gram on the scale.

Anodised aluminium, 7 colours

• Rodbuilders’ Republic winding check for size 18 builds
• Material: anodised aluminium
• Inner diameter: 17 sizes from 8 to 16 mm, in 0.5 mm steps
• Outer diameter: 19.45 mm on every size
• Weight: from 0.94 g in 8 mm to 0.48 g in 16 mm
• 7 colours: Matt Black, Black, Gold, Silver, Red, Cobalt Blue, Titanium Chrome
• Use: closing a carbon grip or a size 18 reel seat thread

Closing a size 18 build cleanly

Compatible with DPS18, TCS18, TRI-AH18 and CRSSD18

The 19.45 mm outer diameter follows the size 18 standards on the market, which removes the step between the ring and the thread. Confirmed references:

• Fuji DPS18, TCS18, DNPSM18
• ALPS TRI-AH18, CAH18LX-WTS, TRI-18KLN, RPD18-IS-N
• American Tackle CRSSD18
• North Fork Composites carbon split grips
• Short straight EVA and cork grips for IPS and VSS16 (20 mm base)

On any other base, the measurement to check is the diameter of the grip base the ring butts against, more than the reel seat size: aim for 19.5 to 20 mm for a flush joint. If you are closing directly on the thread, look at the outlet diameter of your size 18 reel seat.

17 inner diameters, from 8 to 16 mm in 0.5 mm steps

The 0.5 mm step is what makes the RRD18 winding check easy to fit: it covers almost every blank diameter you meet at the rear of a butt section. Measure the blank at the exact spot where the ring will sit, then keep the next size up to leave room for the glue film. A ring that is too wide can be taken up with filled epoxy, but the result will never match a direct fit.

Once the size is chosen, the ring butts against the carbon or EVA grip and hides the joint, which saves you finishing the area with thread and epoxy. Plan on a matching pair of rings if you are closing both the front and the rear of the handle.