The Knuckle is a 10.5" ribbed nozzle with a smooth ball tip followed by a series of progressively larger knuckle-shaped sections. Each main expansion section has a smaller groove through its center, giving the profile a more detailed shape than a standard series of rounded ribs. The nozzle starts with a 0.9" ball tip and a 0.8" valley. The knuckle sections then increase from 1.2" to 1.3", 1.4", and 1.45", before reaching a final 1.8" expansion near the base. Behind the final expansion, the body narrows to a 1.2" retention valley before the safety flange.

Details

• Overall length: 10.5" (26.67 cm)

• Insertable length: approximately 10" (25.4 cm)

• Ball tip: 0.9" (2.29 cm)

• First valley: 0.8" (2.03 cm)

• First knuckle: 1.2" (3.05 cm)

• Second knuckle: 1.3" (3.30 cm)

• Third knuckle: 1.4" (3.56 cm)

• Fourth knuckle: 1.45" (3.68 cm)

• Final expansion: 1.8" (4.57 cm)

• Retention valley: approximately 1.2" (3.05 cm)

Choosing your silicone firmness

For the Knuckle, Bob recommends #10 Medium. This firmness helps the detailed knuckle sections hold their shape while still allowing the piece to flex.

#00-50 Soft is also available if you prefer a softer, more flexible piece.

Color options

#18 and #30 are available in pure translucent silicone.

#00-50 and #10 use a translucent white base and can be mixed with our standard colors.

Please note

The Knuckle has several progressively larger expansion sections and reaches 1.8" at its widest point. The detailed ribbed profile and larger final expansion make it better suited to users who are already comfortable with textured designs and larger diameters.

Anatomy varies, and no single size or shape will work for everyone. Use appropriate lubrication, never force insertion, and stop if you experience pain or significant discomfort. Inspect the nozzle before each use and do not use it if damaged.