Car Cap Caddy Headrest Hat Holder

Overview

The Car Cap Caddy is a headrest-mounted baseball cap holder designed to keep multiple hats neatly stacked, organized, and easy to grab while you’re on the go.

This model mounts around the metal headrest posts and creates a simple cap-stacking shelf behind the seat. The pictured print is user verified and shown installed in a smaller mid-size SUV with multiple caps loaded.

Features

• Headrest-mounted cap storage for cars, trucks, and SUVs
• Stacks multiple baseball caps without tossing them on the seat or floor
• Three size options included for different headrest post spacing
• Optional inserts included to help reduce side-to-side sliding
• No supports required
• PETG recommended for better heat resistance inside vehicles
• User verified with real-world install photos
• Feedback welcome as this design may continue to evolve

Description

The Car Cap Caddy is a simple, practical way to keep your baseball caps organized in your vehicle. Instead of letting hats get crushed, scattered, or buried under other items, this holder gives them a clean dedicated spot behind the headrest.

The design has a low-profile tray shape with a smooth front support and a rear headrest mounting section. It is made to slide around the two metal headrest posts and hold caps in a stacked position, making it useful for daily drivers, work trucks, sports parents, golfers, road trips, and anyone who keeps multiple hats in the vehicle.

Credit for the original idea goes to @KittyPowPow, who suggested this concept on my hat stacker post. I researched common headrest post spacing, post diameter, and the distance from the rods to where the caps sit, but I still consider this a design that could be improved. Constructive feedback is absolutely welcome.

The pictured version works well in my smaller mid-size SUV, and I included three sizes to help fit more vehicle types:

Small – gap range between bars: 100–160 mm, back extrusion: 50 mm
Medium – gap range between bars: 125–185 mm, back extrusion: 60 mm
Large – gap range between bars: 150–210 mm, back extrusion: 70 mm

I also included two insert sizes that can be used if you need help reducing side-to-side movement on your specific headrest setup. They were designed to be more difficult to insert (so they'll stay in place better). They tested well with PETG but I didn't test PLA (more brittle). If you need something a little easier to install due to breakage let me know. 

Assembly Guide

1. Choose the size that best matches your vehicle’s headrest post spacing.
2. Print the Car Cap Caddy in PLA or PETG. PETG is recommended for vehicle heat.
3. Remove the headrest enough to access the metal posts (button on side of its entry base).
4. Slide the caddy mounting slots around the two headrest posts.
5. Reinstall the headrest into position.
6. Add the optional inserts if needed to reduce side-to-side movement.
7. Stack your caps with the brims facing down or outward depending on your preferred fit.

Bill of Materials

No hardware required.

Optional printed parts included:

• Side-to-side stabilizing inserts
• Multiple caddy sizes: Small, Medium, Large

Technical Print Settings

Recommended Material: PETG
Also Tested: PLA
Layer Height: 0.16 mm
Walls: 3
Infill: 20%
Infill Pattern: Gyroid
Supports: No
Variable Layer Height: Yes
Approx. Dimensions: 181 × 181 × 40 mm
Approx. Filament Use: 75 g
Approx. Print Time: 3 hours

Material Notes

PETG is recommended because vehicle interiors can get hot, especially in direct sunlight. PLA may work in cooler conditions, but PETG should provide better strength and heat tolerance for everyday vehicle use.