We do not publish star counts, and we will not invent review numbers here. What we can tell you is which parts get reordered, which ones customers mention by name when they call about something else, and which ones almost never come back. That is what "top-rated" means on this page. These ten are customer favorites across Black Series HQ owners, van builders, and conventional travel-trailer owners, in no particular order.
1. Black Series OEM window struts (pair)
Why: every HQ owner replaces these eventually, and the OEM pair fits without adapting the brackets. Owners buy two pairs: one to fit, one for the drawer.
Price: $25.00. Link: OEM 2 Window Struts for Dual Pane Windows. Measure first with the strut guide.
2. Folding stabilizer leg, adjustable height
Why: stabilizer legs live at the corners and take rocks, curbs, and bad reversing. This one fits most HQ models, folds flat, and is the part customers describe as "the one I should have carried."
Price: $130.00–$141.00. Link: Folding Stabilizer Leg. See the stabilizer legs guide.
3. Victron SmartShunt
Why: the single most common "I wish I had bought this first" comment. It replaces guessing with a percentage, and the Bluetooth app means no panel to install.
Price: from $99.99. Link: Victron SmartShunt 500A/1000A/2000A. Install guide.
4. Victron SmartSolar MPPT 100/30 and 100/50
Why: the default solar controller for RVs. Customers who upgrade from a PWM controller report the difference on the first sunny day, and the units simply do not fail in normal use.
Price: $109.99–$179.99. Link: SmartSolar MPPT 100/30 & 100/50. Which MPPT for RV solar.
5. Victron Orion XS DC-DC charger
Why: it charges a lithium bank from the tow vehicle at 50 A in a box the size of a paperback, runs cool, and configures from the phone. Since it launched it has replaced the Orion-Tr Smart as the customer favorite for trailers.
Price: from $324.99. Link: Orion XS DC-DC Battery Charger. Orion XS vs Orion-Tr Smart.
6. Water pump, 12 V
Why: the direct replacement for the Black Series pump and a drop-in for most campers with a similar footprint. Customers buy it as a spare more often than as a repair, which tells you something.
Price: $99.00. Link: Water Pump 12V. Replacement guide.
7. Cruisemaster DO35 coupling
Why: the off-road coupling fitted to most HQ campers from the factory, and the one owners of other brands upgrade to. Customers mention the quiet ride on corrugations and the ease of hitching at odd angles.
Price: $349.99 (no handbrake) / $389.99 (with handbrake). Links: DO35 no handbrake, DO35 with handbrake. DO35 guide.
8. Dometic Atwood 31011 CO and LP detector
Why: a known brand at a fair price, a hardwired 12 V dual alarm, and the unit most customers choose when their factory detector hits its expiry date.
Price: $44.99. Link: Dometic Atwood 31011 CO & LP Detector. Replacement how-to.
9. HepvO waterless sink trap
Why: it fixes gray-tank smell in the cabin for good, with no water seal to slosh out on rough roads. Customers who fit one in the kitchen come back for the shower.
Price: $34.99. Link: HepvO 1-1/2 in Waterless Trap with Angled Adapter. HepvO install.
10. Eco-Worthy 12 V 280 Ah LiFePO4 battery
Why: the most usable amp-hours per dollar in the store, with Bluetooth monitoring and low-temperature charge protection built in. It is the battery customers choose when they want to go lithium without a Victron-priced bank.
Price: $399.00. Link: Eco-Worthy 12V 280Ah Metal Case LiFePO4. 280 Ah battery guide.
What the list has in common
Look down the ten and a pattern shows: none of them is a luxury. Each one either replaces a part that fails on every camper eventually (struts, stabilizer leg, pump, detector), or fixes a limitation the factory left in (no shunt, a PWM controller, no DC-DC charger, a P-trap that empties on corrugations, a lead-acid battery). That is why they get reordered. Customers do not come back for a second awning light; they come back for the second pair of struts and the SmartShunt for the other trailer.
The other pattern is price. Seven of the ten are under $150. The three that are not (Orion XS, DO35, the 280 Ah battery) are the ones customers describe as "should have done it years ago." If you are deciding where to start, the budget upgrades list sorts these and others by what you can spend.
Honorable mentions
The Carbonogy 12 V roof vent fan ($225.00) for customers who want a MaxxAir-style fan at a lower price; the Victron Blue Smart IP65 charger (from $52.50) as the storage charger everyone ends up with; the CURT breakaway kit ($49.00) because the test light gets people to actually test it; and the recovery tracks ($74.99), which get a thank-you email about once a month.
How we chose
Reorder rate, mentions in support conversations, and return rate. No paid placement, no invented ratings. If a part on this list disappoints you, tell us and it comes off. The live list of what is selling right now is the Best Sellers collection.
Shop this
- Best Sellers (collection)
- Black Series OEM Window Struts — $25.00
- Victron SmartShunt — from $99.99
- Victron Orion XS — from $324.99
- Eco-Worthy 12V 280Ah LiFePO4 — $399.00
- Popular Items (collection)