If you regularly tow your boat, especially on gravel roads, roadworks or unsealed access roads, stones and road debris can be thrown towards the bow and hull while you’re travelling.
A D-Flector stone guard sits between the tow vehicle and boat. Its angled mesh is designed to catch stones thrown from the tow vehicle's tyres and direct them down towards the road, helping protect the boat, trailer and rear of the tow vehicle.
The good news is that choosing the right D-Flector is relatively straightforward. For most trailer boats, the correct model is determined primarily by the overall length of the boat.
What Size D-Flector Stone Guard Do I Need?
D-Flector offers four main D-Series sizes for trailer boats, plus the J100 for jet skis and PWCs.
Each D-Series kit includes a stainless-steel frame, mesh cover, bungee loops, front U-bolts and rear brackets.
Boat length is the starting point, however. If your boat sits close to the boundary between two sizes, or your trailer has an unusual configuration, the individual boat and trailer setup should also be considered. [
How Does a D-Flector Stone Guard Work?
The D-Flector uses angled mesh positioned ahead of the boat's bow. When stones thrown from the tow vehicle's tyres hit the mesh, the angle directs them down towards the road. The flexible mesh also absorbs the impact rather than simply bouncing the stones back towards the tow vehicle.
The stainless-steel frame attaches to the trailer's drawbar and chassis rails using adjustable brackets and U-bolts. The standard mounting system doesn't require the trailer to be cut or welded. Side wings extend the protection around the sides of the hull.
Which D-Flector Fits My Boat?
We've broken down the guide below for popular trailer boat brands available through Northside Marine.
Which D-Flector Fits a Stacer?
For Stacer aluminium boats:
- Proline 359–449
- Territory Striker 359–399
- Seasprite 379
- Assault Pro 409–449
- Outlaw 429–449
- Sea Master 449
- Crossfire 449
- Assault Pro 459–519
- Outlaw 469–529
- Sea Master 481–539
- Crossfire 481–539
- Sea Runner 519–539
- Wild Rider 519–539
- Crossfire 589
- Sea Master 589
- Sea Runner 589
- Wild Rider 589–619
Which D-Flector Fits a Stabicraft?
- Stabicraft 1450 Frontier
- Stabicraft 1450 Explorer
- Stabicraft 1550 Fisher
- Stabicraft 1550 Frontier
- Stabicraft 1850 Fisher
- Stabicraft 1850 Supercab
- Stabicraft 2050 Frontier
- Stabicraft 2050 Supercab
- Stabicraft 2050 Treker
- Stabicraft 2350 Supercab
- Stabicraft 2350 Ultracab
- Stabicraft 2350 Ultra Centrecab
- Stabicraft 2500 Ultracab XL
- Stabicraft 2750 Ultra Centrecab
Which D-Flector Fits a Formosa?
- Formosa GRT 425
- Formosa GRT 455
- Formosa SRT 495
- Formosa SRT 525
- Formosa SRT 565 Centre Console
- Formosa SRT 565 Side Console
- Formosa SRT 565 X Bowrider
- Formosa SRT 595 X Bowrider
- Formosa SRT 635 Centre Cabin
- Formosa SRT 675 Enclosed Centre Cabin
The Formosa GRT 455 sits particularly close to a sizing point. The supplied fitment guide recommends the D500, with the D400 listed as an alternative.
Which D-Flector Fits a Surtees?
- Surtees 495 Pro Fisher
- Surtees 495 Workmate
- Surtees 540 Pro Fisher
- Surtees 540 Workmate Hardtop Pro
- Surtees 575 Pro Fisher
- Surtees 575 Workmate Pro
- Surtees 610 Pro Fisher
- Surtees 610 Workmate
- Surtees 620 Game Fisher
- Surtees 670 Game Fisher
- Surtees 720 Game Fisher
- Surtees 770 Game Fisher XL
- Surtees 800 Game Fisher
Which D-Flector Fits a Haines Signature?
- Haines Signature 525F
- Haines Signature 543SF
- Haines Signature 545F
- Haines Signature 550BR
- Haines Signature 620F
- Haines Signature 620BRX
- Haines Signature 640F
- Haines Signature 680F
Which D-Flector Fits a Highfield?
For Highfield Sport and Patrol RIBs transported on a trailer:
- Highfield Sport 460
- Highfield Sport 520
- Highfield Patrol 460
- Highfield Patrol 500
- Highfield Patrol 540
- Highfield Sport 560
- Highfield Patrol 600
- Highfield Sport 660, 700, 760 and 800
- Highfield Patrol 660, 700 and 760
- Highfield ADV7
The Highfield Sport 660 and Patrol 660 sit just beyond the 6.5m D600 size boundary. The supplied guide therefore recommends the D700, while also identifying the D600 as an alternative.
For the larger Highfield Sport 900, Patrol 860 and ADV9, the guide specifies a D700 together with the BKT011 long-reach rear bracket kit.
Which D-Flector Fits a Jeanneau?
For the trailerable Jeanneau models included in the guide:
- Jeanneau Merry Fisher 605
- Jeanneau Merry Fisher 695
- Jeanneau Merry Fisher 695 Sport
- Jeanneau Merry Fisher 795
- Jeanneau Merry Fisher 795 Sport
- Jeanneau Cap Camarat 7.5 WA
- Jeanneau Cap Camarat 7.5 CC
The supplied guide doesn't provide a mapping for the Merry Fisher 895 and larger models, Cap Camarat 9.0 and larger models, or Jeanneau DB and TH models. These boats are generally no trailerable.
What If My Boat Is Between Two D-Flector Sizes?
Start with the boat's overall length, but don't rely on length alone if the boat falls right on a sizing boundary.
The main size ranges are:
- Up to 4.5m: D400
- 4.6–5.5m: D500
- 5.6–6.5m: D600
- 6.6–8.5m: D700
For an unusual hull shape or older trailer configuration, the supplied guide recommends confirming fitment using both the boat length and a photo of the trailer.
Which D-Flector Do I Need for a Boat Over 8.5 Metres?
The normal D700 sizing range extends from 6.6m to 8.5m.
For the Highfield Sport 900, Patrol 860 and ADV9, which are outside that standard range, the supplied recommendations specify a D700 with the BKT011 long-reach rear kit.
For other boats outside the normal sizing range, fitment should be checked specifically for the boat and trailer rather than choosing solely according to length.
Can You Replace the Mesh on a D-Flector Stone Guard?
Yes. The mesh cover is replaceable, so the stainless-steel frame can remain in place. Replacement bungee hook packs, rear brackets and U-bolt sets are also available as separate components in the D-Flector fitment guide.
Are D-Flector Stone Guards Designed for Australian Conditions?
According to the supplied D-Flector information, the company has been Australian owned since 2007, with its guards designed and made in Moorabbin, Victoria.
The document lists testing for:
- Salt spray to ASTM B117
- Stone-chip resistance to ASTM D3170
- Thermal cycling to IEC 60068-2
- Vibration to ISO 16750-3:2007
- Mesh UV exposure to ASTM D4329
The document also references ISO 9001:2015 quality management and states that D-Flector guards have a three-year warranty.
How Do I Know Which D-Flector Is Right for My Boat?
The simplest place to start is with your boat's overall length.
For most trailer boats:
Up to 4.5m = D400
4.6–5.5m = D500
5.6–6.5m = D600
6.6–8.5m = D700
If your boat is close to the boundary between two sizes, is longer than the standard D700 range or sits on an unusual trailer, check the individual boat and trailer combination before deciding.
That way, you're choosing a stone guard to suit the boat you're actually towing, rather than simply choosing one by brand or model name.
Still Not Sure Which D-Flector You Need?
Boat length is the best place to start, but your trailer setup can also affect the correct fitment. If your boat sits between two D-Flector sizes, or you have an unusual trailer configuration, speak with the Northside Marine team before choosing.
