Wiper blades are the cheapest safety-relevant part on a European car, and the one most owners ignore until a downpour on the freeway decides for them. Bosch is an original-equipment wiper supplier to the European makers, and Aerotwin is its flat-blade design. Here is how it works, what the A-, AP- and rear part numbers mean, how to measure your blades, and a size table of every Bosch blade we stock.
01 What an Aerotwin flat blade is and why it replaced the frame blade
A conventional blade is a small metal bridge: the arm presses on the centre of a frame, hinged claws split the load, and the rubber touches the glass at a handful of points. Pressure concentrates at the claws, and at highway speed the frame acts as a sail, so the blade lifts and chatters when you need it planted.
An Aerotwin has no frame. Two spring-steel rails inside the rubber are pre-curved to match the windscreen, so pressure is spread evenly along the whole wiping edge; an integrated spoiler uses airflow to press the blade down, and there are no hinges to seize. Carmakers changed their arm connectors when they adopted it, which is why an Aerotwin set is sold for a specific vehicle with the adaptor already fitted.
02 Reading Bosch wiper blade part numbers
A-series sets: two front blades, vehicle-specific
A code such as A930S is A for Aerotwin, a three-digit application number and S for set. The box holds both front blades, usually unequal: the A930S is a 600 mm blade and a 475 mm blade. The application number encodes the arm connector, rail curvature and spoiler position. The A205S and A929S are also 600 mm plus 475 mm; the A826S and A054S pair two 600 mm blades.
AP-series singles: one blade, universal fitting
AP is Bosch's Aerotwin Plus range of single blades; the U marks a universal fitting, with adaptors in the box. The number is the length, two digits in inches and three in millimetres: the AP24U is 24 inches, or 600 mm; the AP19U is 19 inches, or 475 mm; the AP475U is 475 mm.
Rear blades: the H tells you where it goes
An H in the code marks a rear blade. The AM30H and H301 are both 300 mm; the A334H is 330 mm. Two 300 mm rear blades exist because rear arms use different fixings: the H301 is a conventional-style blade, the AM30H and A334H are flat blades.
An A930S and an A205S both hold a 600 mm and a 475 mm blade, but their connectors differ and neither clips onto the other's arms. Part number first; lengths second.
03 How to measure your current wiper blades
If the blades are Bosch, the part number is printed on the blade body, usually along the spoiler or an end cap; otherwise, a tape measure will do.
- Measure the blade, not the arm — end to end of the blade body, in millimetres. Bosch quotes nominal lengths: 598 mm is a 600 mm blade.
- Measure both front blades — many European cars run an unequal pair, and some keep their left-hand-drive wiper layout in right-hand-drive form, so the long blade is not always on the driver's side.
- Look at the connector — hook, push-button, pinch tab, side pin or bayonet clip.
- Don't round to the nearest size — if the tape says 550 mm, or anything not in the table below, use the vehicle selector rather than the closest match; the arm and screen decide the part.
04 Bosch Aerotwin size table: every blade we stock
Lengths are taken from the product; for sets, the longer blade is listed first.
| Part number | Range | Length | Position |
|---|---|---|---|
| Bosch A826S | Aerotwin set of 2 | 600 mm + 600 mm | Front pair |
| Bosch A054S | Aerotwin set of 2 | 600 mm + 600 mm | Front pair |
| Bosch A930S | Aerotwin set of 2 | 600 mm + 475 mm | Front pair |
| Bosch A205S | Aerotwin set of 2 | 600 mm + 475 mm | Front pair |
| Bosch A929S | Aerotwin set of 2 | 600 mm + 475 mm | Front pair |
| Bosch AP24U | Aerotwin Plus single | 600 mm | Front |
| Bosch AP19U | Aerotwin Plus single | 475 mm | Front |
| Bosch AP475U | Aerotwin Plus single | 475 mm | Front |
| Bosch AM30H | Rear flat blade | 300 mm | Rear |
| Bosch H301 | Rear conventional | 300 mm | Rear |
| Bosch A334H | Rear flat blade | 330 mm | Rear |
The full range is under wiper blades; the rest of the brand is on the Bosch page.
05 Signs your wiper blades need replacing
Clean the glass and the blade edge first; if these persist, the rubber is finished.
- Streaks and lines — a nick in the edge leaves the same unwiped line on every sweep.
- Smearing one way — the edge has taken a set and no longer flips on the return stroke.
- Chatter and judder — hardened rubber skips across the glass instead of gliding.
- Squeal on a wet screen — the edge has hardened; squeal on a dry screen is normal.
- Visible damage — a split strip, a cracked spoiler, or a corner that no longer touches the glass.
Australian sun is what ages wiper rubber: UV and heat harden the compound, and a car parked outdoors through a Queensland or Western Australian summer has its blades baking on hot glass every day. Check them every six months and expect to replace them about yearly; a garaged car gets more, a car on a Darwin street gets less. If the inside of the screen fogs too, suspect a clogged cabin filter rather than the wipers.
06 Fitting tips
Swapping a blade needs no tools, but a wiper arm under spring tension can crack a windscreen, so fold a towel on the glass under the arm before lifting it.
- Find the service position — on many European models the arms park under the bonnet edge and only lift once the wipers are in the service position described in the owner's manual. Never force an arm; let a workshop free a seized one.
- Study the old blade first — note how it releases and which way round it sits, press the tab and slide it off. The long blade goes back where it came from.
- Listen for the click — the adaptor should lock; pull gently to confirm, then lower the arm by hand rather than letting it spring onto the glass.
- Finish properly — remove any protective sleeve, wet the screen and run one cycle to check the sweep is even and quiet.
- Do both — front blades wear as a pair and mismatched rubber wipes unevenly where the sweeps overlap; with singles, buy two.
07 Confirm the exact set with the vehicle selector
The selector settles it. Open wiper blades, choose make, model and variant, and the list filters to blades with TecDoc-confirmed fitment for Australian-market cars; the product page then shows a "fits your vehicle" confirmation and a compatible-vehicle table. It also separates same-length sets with different connectors, and the two 300 mm rear fittings. Blades are light, so they go Australia Post Parcel Post or Express Post, your choice at checkout; the delivery estimator on each product page shows options and cost for your postcode. Unsure between two? Contact us with your VIN; more guides are in the resources hub.
FAQ Common questions
What sizes are in a Bosch A930S set?
The Bosch A930S is an Aerotwin front set: one 600 mm blade and one 475 mm blade. The S means set, so one box covers both front wipers. Confirm it with the vehicle selector, because several Bosch sets share those lengths with different connectors.
Are the Bosch A205S and A930S interchangeable?
No. Both contain a 600 mm and a 475 mm blade, but the application number identifies a different arm connector and blade profile, so each set clips only onto the arms it was designed for. Go by the part number the vehicle selector confirms.
What is the Bosch AP24U?
The AP24U is a single Bosch Aerotwin Plus flat blade, 600 mm long, supplied with universal adaptors; the 24 is the length in inches. It suits replacing one front blade, or pairing with the 475 mm AP19U or AP475U for an unequal front set. Confirm fitment with the vehicle selector.
Which Bosch rear wiper blade is 300 mm?
Two: the Bosch AM30H and H301 are both 300 mm rear blades, while the A334H is 330 mm. The AM30H is a flat blade and the H301 a conventional-style blade, with different fixings. The vehicle selector shows which one is confirmed for your car.
How often should wiper blades be replaced in Australia?
There is no fixed interval; sun exposure matters more than kilometres. Heat and UV harden the rubber, so a car parked outdoors in a hot climate needs blades sooner than a garaged one. Inspect every six months, expect to replace about yearly, and sooner if they streak, chatter or squeal on a clean wet screen.
