Coupling heads and Overrun devices
Coupling heads and coupling units, sometimes also called overrun devices are all vital accessories when it commes to attaching the trailer onto your vehicle in a safe manner. At our online store, you will find plenty of coupling heads and coupling units, which have been produced by renowned manufacturers such as AL-KO, KNOTT, WINTERHOFF and STEELPRESS. The accessories in question boast a GVW values ranging between 700 and 3500 and are available at very affordable prices. If you want to travel risk-free with your trailer, simply get your hands on a coupling unit today and save yourself from all the hassle.

Shock absorber for overrun device/brake AL-KO 161S (old type) for 1600kg trailer

- For the coupling unit:

AL-KO 7/13 pin plug holder - universal size

2,49 €1045 PTS
- Model:
- Intended for::

KNOTT KS30 ball hitch with stabilizer for 3000kg trailer with 35-50mm tubular drawbar


WINTERHOFF WW8-E ball hitch for 800kg trailer with 50mm square drawbar

13,99 €5873 PTS

AL-KO 2.8VB1 overrun device with AK351 hitch for 3500kg trailer with square drawbar

888,99 €373189 PTS
- Drawbar profile:
- Drawbar:
- GVW:
- Nose load:

KNOTT overrun absorber for KF7,5 750 kg

- For the coupling unit:

WINTERHOFF WW8-G ball hitch for 800kg trailer with 60mm square drawbar

14,49 €6083 PTS

WINTERHOFF WW8-Y ball hitch for 800kg trailer with V-type drawbar

16,99 €7132 PTS

WINTERHOFF WW8-A ball hitch for 800kg trailer with 50mm tubular drawbar

15,39 €6461 PTS

STEELPRESS ZSK-0750H ball hitch for 750kg trailer with 50mm square drawbar

12,89 €5411 PTS

Bellow for overrun device AL-KO 161S/251S/251G FI50

9,49 €3984 PTS

AL-KO 251S overrun device with AK270 hitch for 2700 kg trailer with V-type drawbar

289,59 €121567 PTS
- Drawbar profile:
- GVW:
- Nose load:

AL-KO 90S/3 overrun device with AK161 hitch for 1000 kg trailer with V-type drawbar

257,29 €108008 PTS
- Drawbar profile:
- GVW:
- Nose load:

AL-KO AK7 ball hitch for 750kg trailer with 60mm square drawbar

15,79 €6628 PTS

KNOTT KF27B overrun device with K27A hitch for 2700 kg trailer with V-type drawbar

321,19 €134832 PTS
- Drawbar profile:
- GVW:
- Nose load:

KNOTT K7.5-L ball hitch for 750kg trailer with 60mm square drawbar

21,29 €8937 PTS

KNOTT KQ14-A ball hitch for 1400kg trailer with 50mm square drawbar

30,99 €13009 PTS

KNOTT K27-A ball hitch for a 2700kg trailer with a 50mm pipe drawbar, cast iron

57,89 €24302 PTS

WINTERHOFF WW8-C ball hitch for 800kg trailer with 70mm tubular drawbar

16,29 €6838 PTS

WINTERHOFF WW8-B ball hitch for 800kg trailer with 60mm tubular drawbar

16,49 €6922 PTS

WINTERHOFF WW8-H ball hitch for 800kg trailer with 70mm square drawbar

16,99 €7132 PTS

Plug holder cover WINTERHOFF W1707 universal 7-PIN and 13-PIN for trailer

1,99 €835 PTS

WINTERHOFF WW150-VG ball hitch for 1500kg trailer with 70mm square drawbar

32,99 €13849 PTS

AL-KO AK301 ball hitch for 3000kg trailer with 50mm pipe drawbar, cast iron

89,79 €37693 PTS

Rubber bellows - KNOTT KF7,5-KF30 protective rubber

9,99 €4194 PTS

Rubber bellows - KNOTT KF27-KF35 safety rubber

9,99 €4194 PTS

Shock absorber for overrun device AL-KO 251S 2700 kg - new model

68,99 €28961 PTS
- For the coupling unit:
- GVW:

KNOTT K14-A ball hitch for 1400kg trailer with 50mm tubular drawbar

31,59 €13261 PTS

AL-KO 161S overrun device with AK161 hitch for 1600kg trailer with square drawbar

391,99 €164553 PTS
- Drawbar profile:
- GVW:
- Nose load:

AL-KO 161S overrun device with AK161 hitch for 1600 kg trailer with V-type drawbar

282,99 €118796 PTS
- Drawbar profile:
- GVW:
- Nose load:

AL-KO 251G overrun device with AK301 hitch for 3000 kg trailer with V-type drawbar

403,69 €169465 PTS
- Drawbar profile:
- GVW:
- Nose load:

AL-KO 251S overrun device with AK270 hitch for 2600kg trailer with square drawbar

421,29 €176853 PTS
- Drawbar profile:
- Drawbar:
- GVW:
- Nose load:

AL-KO AK351 ball hitch for 3500kg trailer with 60mm pipe drawbar, cast iron


KNOTT KF13E overrun device with KK14B hitch for 1400 kg trailer with V-type drawbar

315,99 €132649 PTS
- Drawbar profile:
- GVW:
- Nose load:

KNOTT KF20A overrun device with K20B hitch for 2000 kg trailer with V-type drawbar

302,79 €127108 PTS
- Drawbar profile:
- GVW:
- Nose load:

KNOTT KF17A overrun device with K20B hitch for 1700 kg trailer with V-type drawbar

279,09 €117159 PTS
- Drawbar profile:
- GVW:
- Nose load:

KNOTT KFG30A overrun device with K35A hitch for 3000 kg trailer with V-type drawbar

489,69 €205567 PTS
- Drawbar profile:
- GVW:
- Nose load:

KNOTT KFG35D overrun device with K35C hitch for 3500 kg trailer with V-type drawbar

698,19 €293093 PTS
- Drawbar profile:
- GVW:
- Nose load:

AL-KO AK270 ball hitch for 2700kg trailer with 50mm tubular drawbar

73,99 €31060 PTS

Shock absorber for trailers AL-KO 101VB/90S

88,99 €37357 PTS
- For the coupling unit:

AL-KO 60S/2 overrun device with AK161 hitch for 750kg trailer with V-shaped drawbar

248,99 €104524 PTS
- Drawbar profile:
- GVW:
- Nose load:

AL-KO 161S overrun device with AK161 hitch for 1600kg trailer with square drawbar

410,99 €172529 PTS
- Drawbar profile:
- Drawbar:
- GVW:
- Nose load:

WINTERHOFF WW13-N ball hitch for 1500kg trailer with 45mm tubular drawbar

40,99 €17207 PTS

WINTERHOFF WW150-RB ball hitch for 1500kg trailer with 50mm tubular drawbar

39,49 €16578 PTS

Support bracket for overrun device AL-KO 150 mm

8,99 €3774 PTS
- Material:
- Height:

AL-KO AKS3004 ball hitch with stabilizer for 3000kg trailer with 50mm tubular drawbar


AL-KO AK161 ball hitch for 1600kg trailer with 50mm tubular drawbar

68,99 €28961 PTS

KNOTT KF27B overrun device with K27A hitch for a 2700 kg trailer with a V-shaped drawbar and a support wheel bracket

342,29 €143690 PTS
- Drawbar profile:
- GVW:
- Nose load:

Trailer bellow - rubber protection for KNOTT overrun device KFG35

17,99 €7552 PTS

STEELPRESS ZSK-0750J ball hitch for 750kg trailer with 70mm square drawbar

23,69 €9945 PTS

STEELPRESS ZSK-0750C ball hitch for 750kg trailer with 50mm tubular drawbar

21,99 €9231 PTS

Overrun shock absorber 251S 2600 kg - old model

115,99 €48691 PTS
- For the coupling unit:
- GVW:

Trailer overrun damper 161S 1600 kg - new model

96,99 €40715 PTS
- For the coupling unit:

Overrun brake damper 251G 3000 kg

- For the coupling unit:

AL-KO overrun damper 2.8 VB/1 3500 kg

- For the coupling unit:
- 1
- 2

Coupling heads
Coupling heads are used to attach the trailer onto a vehicle. There are many different types of coupling heads - coupling heads for V-shaped drawbars, coupling heads for T-shaped drawbars, coupling heads for pipe-shaped drawbars etc. The main point of difference between them however, is their maximum permissible GVW value, maximum load capacity of the coupling hook and last but not least, their spacing between mounting holes, which can all vary from model to model. In the case of coupling heads available in our online store, all the information that you need for individual coupling models can be found on the product's page.Coupling heads are equipped with a wear indicator, which helps to assess when the accessory in questions needs replacing. Another helpful source of information about the coupling head is the coupling correctness indicator, with the aid of which trailer users assess whether or not the trailer has been correctly connected onto a vehicle.
Trailer coupling units
Trailer coupling units also known as overrun devices are trailer accessories which are made up of not only a braking system but also of a coupling head and a steel casing, which connects the device together. It is possible to replace individual coupling unit parts rather than then whole set. It is also possible to equip the unit with shock absorbers.Coupling units for heavy-duty braked trailers with a GVW of 750kg or more are mounted onto drawbars of regular car trailers and tow trucks. There is no need to assemble a coupling unit onto a light-duty trailer, as it is required neither by law nor by sheer laws of physics, which would otherwise demand for a heavy-duty trailer to be equipped with such an accessory. Using a coupling unit will therefore increase safety levels when your trailer is in drive mode and will thus significantly decrease the force exerted on your car's brake system.
Car trailer coupling heads and coupling units
The more a car trailer coupling unit is used, the more likely it is that it is going to fall victim of natural wear and tear. Before you head off on a long trip, it is worth checking the wear indicator of the coupling unit and the coupling head.Coupling units are the only trailer element apart from the brake cord which connect the trailer with the towing vehicle. Assemblying the trailer coupling unit correctly is the first step which needs to be taken in order to reassure oneself of a safe drive. Here, at Unitrailer, we care about high quality products. It is for this reason that we sell only AL-KO, KNOTT, WINTERHOFF and STEELPRESS coupling units, as they offer the highest possible quality on the market. Choose the right coupling unit today and take care of your brake system the right way!