To order the right Battcar system, match the system size (AA, A, B, or C) to your mainsail's total sail area, then order enough track to cover the mast luff, an endstop kit for each end, and one car for the headboard plus one for every full-length batten. This guide walks through the four ordering steps so your batten car system fits your mast, handles the load, and raises and lowers smoothly.
Battcar system sizes at a glance
| System Size | Max Sail Area — Monohull (ft² / m²) | Max Sail Area — Multihull (ft² / m²) | Typical Boat Length (ft / m) |
|---|---|---|---|
| AA | 350 / 32 | 275 / 25 | to 37 / to 11.3 |
| A | 600 / 56 | 500 / 46 | 37–50 / 11.3–15.2 |
| B | 900 / 83 | 700 / 65 | 50–60 / 15.2–18.3 |
| C | 1940 / 180 | 1510 / 140 | 60–90 / 18.3–27 |
Multihull ratings run smaller because catamarans and trimarans load their mainsails more aggressively. Boat length is a guide only — always size by actual sail area.
What is a Battcar system and why does mine matter?
A Battcar (batten car) system replaces the sliders in your mast track with low-friction cars that carry the mainsail and its full-length battens. The cars ride on a dedicated aluminum track, letting the sail hoist, reef, and douse smoothly even under heavy load. Choosing the correct size is what keeps the system reliable: an undersized system will bind or wear out, while the right size handles the load and slides freely.
Tip: Need a lower car stack height at the mast? Ask us about Switch T-Track Battcar Systems for a more compact solution.
How do I choose the correct system size?
There are four Battcar system sizes — AA, A, B, and C — sized to the total sail area of your mainsail. Find your mainsail's area, then read the "at a glance" table above to select the smallest system that covers it. Use the monohull column for keelboats and the multihull column for catamarans and trimarans, since multihulls load the sail harder and step down a size for the same area.
How much track do I need, and how do I mount it?
Track is ordered in fixed-length sections, and the number of sections depends on your mainsail luff length. Use the luff-length chart below to count sections; note that track extends above the sail luff, and using screwpin endstop kits will increase the required length.
| System AA — Mainsail luff length | # of 3817 track sections | System A — Mainsail luff length | # of 3807 track sections | ||
|---|---|---|---|---|---|
| ft | m | ft | m | ||
| 19'7" - 26'3" | 5.98 - 8.00 | 4 | 26'4" - 33' | 8.03 - 10.06 | 5 |
| 26'4" - 33' | 8.03 - 10.06 | 5 | 33'1" - 39'9" | 10.08 - 12.11 | 6 |
| 33'1" - 39'9" | 10.08 - 12.11 | 6 | 39'10" - 46'5" | 12.13 - 14.16 | 7 |
| 39'10" - 46'5" | 12.13 - 14.16 | 7 | 46'6" - 53'2" | 14.19 - 16.21 | 8 |
| 53'3" - 59'11" | 16.24 - 18.26 | 9 | |||
| System B — Mainsail luff length | # of 3844 track sections | System C — Mainsail luff length | # of 3853 track sections | ||
|---|---|---|---|---|---|
| ft | m | ft | m | ||
| 39'10" - 46'6" | 12.13 - 14.17 | 7 | 53'8" - 60'5" | 16.36 - 18.42 | 9 |
| 46'7" - 53'3" | 14.19 - 16.23 | 8 | 60'6" - 67'3" | 18.45 - 20.50 | 10 |
| 53'4" - 60' | 16.25 - 18.29 | 9 | 67'4" - 74'1" | 20.53 - 22.58 | 11 |
| 60'1" - 66'9" | 18.31 - 20.35 | 10 | 74'2" - 80'11" | 22.61 - 24.66 | 12 |
| 66'10" - 73'6" | 20.37 - 22.44 | 11 | 81' - 87'9" | 24.69 - 26.74 | 13 |
| 87'10" - 94'7" | 26.77 - 28.82 | 14 | |||
| 94'8" - 101'5" | 28.85 - 30.90 | 15 | |||
Note: track extends above the sail luff, and using screwpin endstop kits will increase lengths.
Track mounting options
- Slug-mount (most popular): each track section requires one slug-mount kit. Choose a slug profile that matches your mast's bolt-rope groove.
- Drill-tap mount: ideal for masts without a bolt-rope groove. Use one splice link per track joint for a secure connection.
Which endstop kit and cars should I order?
Endstops secure the Battcar system at both ends of the track, and you choose the car type based on budget and performance. Order an endstop kit plus one headboard car, one Battcar per full-length batten, and intermediate cars sized to your sail.
Endstop kit choices
- Quick-release kit: includes a screwpin or pinstop lower endstop and a fixed top endstop for easier removal.
- Fixed kit: comes with two fixed endstops for a more permanent installation.
How many cars?
- 1 headboard car
- 1 Battcar for each full-length batten
- Intermediate cars based on the batten spacing chart below
| Distance Between Battens* | Intermediate Cars Between Battens | |
|---|---|---|
| ft | m | |
| 8 or less | 2.4 or less | 1 |
| 9–13 | 2.7–4 | 2 |
| 14–16 | 4.3–4.9 | 3 |
*Boats without full battens should use 1 intermediate CB or Slider car per 1.2 m (4 ft) and no Battcars.
Car system types
- CB (Captive Ball) system: premium low-friction solution for fast hoisting, reefing, and dousing. Best performance under load.
- Combination system: CB cars for the headboard and battens, with Slider intermediate cars to reduce cost while retaining high-load capacity where it matters.
- Slider system: budget-friendly option with all-Slider components. Easy sail handling with reduced risk of jamming.
Frequently asked questions
What are the four Battcar system sizes?
Harken Battcar systems come in AA, A, B, and C. You pick the size from your mainsail's total sail area — AA for the smallest boats up to C for mainsails as large as 1,940 ft² (180 m²) on a monohull.
How do I know how many track sections to order?
Measure your mainsail luff length and read it against the luff-length chart for your system size. Remember the track extends above the sail luff, and screwpin endstop kits add a little more length.
What's the difference between slug-mount and drill-tap track?
Slug-mount is the most popular option and slides into your mast's bolt-rope groove using one slug-mount kit per section. Drill-tap mounting is for masts without a bolt-rope groove and uses a splice link at each track joint.
How many cars does a complete system need?
You need one headboard car, one Battcar for every full-length batten, and intermediate cars sized by the distance between battens — one to three intermediate cars per gap depending on spacing.
Which car type gives the smoothest hoist?
The CB (Captive Ball) system offers the lowest friction and best performance under load. A Combination system mixes CB and Slider cars to cut cost, and an all-Slider system is the budget choice with easy handling.
What if my boat doesn't have full-length battens?
For sails without full battens, skip the Battcars and use one intermediate CB or Slider car per 1.2 m (4 ft) of luff instead.