Half Dome Limestone M/L vs Boreo White M/L

Buy the Black Diamond Half Dome, Limestone, size Medium/Large, UPC 793661151357, when you want the gray helmet with orange clips the card describes as a hybrid EPS shell with a wheel adjuster. Buy the Petzl Boreo, white, size Medium/Large, when you want the white helmet whose description prints an M/L weight of 295 g and a head size of 53 to 61 cm. One card never prints the new weight. The other card prints two weights and only one of them belongs to this size.

Short version. A belay device and a crash pad are the rest of a climbing setup, not the helmet. Two harnesses sit on the waist, not on the head. Two bike helmets are a different sport and a different standard. Match the Half Dome Limestone M/L or the white Boreo M/L before you match the word helmet.

The Black Diamond title is a Half Dome climbing helmet in Limestone, Medium/Large. The model cell is the words Black Diamond Half Dome Climbing Helmet. There is no numeric part in that cell. The UPC 793661151357 is the reorder string you actually have. The brand cell says Black Diamond. The color cell says Limestone. The size cell says Medium/Large. The outer-material cell says Polycarbonate. The special-feature cell says Ventilation. The uses say climbing. The photo is a gray shell with orange clips, which is what this Limestone card shows. If the helmet in the mail is tropic green or orange, the color cell was not what shipped.

The features name a hybrid EPS construction, a wheel adjuster, and headlamp clips. Hybrid and EPS are the foam-and-shell story. The description says weight savings of more than 40 grams and does not print the new weight. More than 40 grams off an unnamed older weight is not a specification. You cannot subtract 40 from a number the card never stated. A different color card, the Tropic small/medium Half Dome on another ASIN, prints Weight S/M of 310 g and M/L of 340 g. That card is not this Limestone listing, and its usual product image is not a usable photo, so it does not get a buy button here. Cite 340 g only as the other card's M/L line. Do not paste it into the Limestone detail block. Weigh the helmet you unpack if the grams matter.

Medium/Large is the size cell. A small/medium Half Dome is a different size and often a different fit range. The card does not print a centimeter range next to Medium/Large on this Limestone listing. Do not invent 53 to 61 cm from the Petzl card and assign it to Black Diamond. The wheel adjuster is the fit system the features name. It is not a size label. Polycarbonate is the outer cell. EPS is in the feature language. Ventilation is the special feature, which means ports, not a certification. The card does not print CE, UIAA, or EN 12492 in the cells used for this color. If a hangtag in the box shows those marks, the hangtag is the source. The Amazon cell is not.

The Petzl title is a Boreo helmet, white, Medium/Large, and the title also says SS23. The model cell says Petzl Boreo Helmet. Again the model cell is a name, not a numeric part like A042HA00. A red small/medium card uses A042HA00, and that part number does not belong to this white M/L row. Do not reorder A042HA00 and expect this white helmet. The color cell says WHITE. The size cell says Medium/Large. The brand cell says Petzl. The photo is a white shell with the Petzl mark and a chin strap. SS23 is a season code in the title. It is not a size.

The description prints two sizes. Small/medium is 48 to 58 cm and 285 g. Medium/large is 53 to 61 cm and 295 g. This row is Medium/Large, so 295 g and 53 to 61 cm are the lines that match the size cell. 285 g is the other size. Quoting 285 g for this white M/L helmet is how the weights get swapped. The overlap from 53 to 58 cm means some heads fit both Petzl sizes. The weight still follows the size you ordered, not the overlap. Sibling cards mention CE EN 12492 and UIAA, and they describe an ABS shell with EPP and EPS foam and four headlamp clips. Those certification strings and the foam stack live on the sibling writeups. This white card's description is the place that prints the grams and the centimeters. Use that. If the hangtag shows EN 12492, you can say the hangtag showed it. Do not pretend a sibling's model code is printed in this model cell.

Four headlamp clips, if you are citing the family description, are a mounting claim. This white card's photo shows a climbing helmet with strap hardware, not a headlamp. A headlamp is a different purchase. The Bindi and NU25 article is a different desk day. ABS, EPP, and EPS are three material words. The Black Diamond outer cell says polycarbonate and the feature says hybrid EPS. The Petzl family language says ABS plus EPP plus EPS. Those are not the same sentence. Do not merge them into one foam recipe for both helmets. White is the color cell. Limestone is the other helmet's color. They are both light-colored in a loose sense and they are not the same paint. The photos are gray-with-orange versus white.

Who should buy the Half Dome, and who should buy the Boreo?

Buy the Limestone Half Dome if Medium/Large is your Black Diamond size, you want the gray shell with the orange clips, and you will not invent a gram weight from the phrase "more than 40 grams." Buy it if the UPC 793661151357 is the barcode you meant. Buy the white Boreo if your head is in the 53 to 61 cm band and you want the 295 g line that matches Medium/Large. Buy the Petzl if white is the color and SS23 in the title does not scare you into thinking it is a size. Buy neither if you needed a bike helmet, a harness, or a belay device. Buy neither if you needed the red Petzl S/M part A042HA00 or the Tropic Half Dome's printed grams.

Do not buy the Half Dome in Medium/Large because the Tropic card said 340 g and you wanted that number in Limestone. Order Limestone and weigh it. Do not buy the Boreo M/L and tell a partner it weighs 285 g. That number is the S/M line in the same description. Do not buy a small/medium of either helmet because the word helmet matched.

What the Limestone Half Dome is actually for

This card is one climbing helmet, size Medium/Large, color Limestone. The wheel adjuster and the headlamp clips are the features you can cite. Ventilation is the special-feature cell, so the shell has ports. Polycarbonate is the outer. Hybrid EPS is the construction phrase. The 40-gram savings line is marketing until it names the previous weight. It does not. A climbing helmet is for impacts the standard on the hangtag covers, and this Amazon cell does not print the standard. Look at the hangtag in the box before you cite EN or UIAA. If the tag is missing, the card will not replace it.

Limestone is a gray. The orange clips in the photo are the color accent, not a second color cell. The size cell is Medium/Large, not a unisex sentence and not a youth size. A youth helmet is a different model. The model cell's full sentence is useless for a reorder because every Half Dome color could share that sentence. The UPC is the identifier. Headlamp clips do not include a headlamp. You still buy the lamp. The chin strap is in the photo of this family of helmets. This card does not print a strap-break strength. Do not invent one.

What the white Boreo is actually for

This card is one white Petzl Boreo in Medium/Large. The description's matching numbers are 53 to 61 cm and 295 g. SS23 in the title is a season marker. WHITE is the color cell. The photo shows the Petzl mark on a white shell and a buckle on the chin strap. That is the helmet you should receive. A red or orange Boreo is a different color row. A042HA00 is a different size's part number. Four clips, ABS, EPP, and EPS are the family language from sibling cards. Use them as sibling language. Use 295 g as this size's description line.

The overlap with the S/M range, 48 to 58 cm against 53 to 61 cm, is why two people with a 55 cm head can wear different sizes and why the weight still depends on the size row. If you are between sizes, the card does not tell you which to prefer. Try the helmet. The 295 g figure is a published description line, not a promise that your unit will hit that gram on a kitchen scale. Production scatter exists, and the card does not print a tolerance. If the helmet is obviously a different size, the size cell was ignored by the shipper. Send it back. Medium/Large is what this row is.

How to wear them without mixing the two jobs

Fit the Half Dome with the wheel the features name, low enough that the shell covers the forehead, and fasten the chin strap. The card does not print a how-to. A helmet worn back on the crown is not the fit the size cell implied. Clip a headlamp only into the clips the helmet has. Do not tape a lamp to the vents and call it the feature. Retire a climbing helmet after a significant impact. The card does not print a service life in years. Read the hangtag. Do not use this climbing helmet as the bike helmet in the Giro and Bell article. The standards are not the same sentence, and this card did not claim a bike certification.

Fit the Boreo to the 53 to 61 cm line if that is your measurement, and use 295 g only as the description's M/L weight. Fasten the strap in the photo's buckle. Do not cite 285 g after you ordered M/L. Do not cite A042HA00 as the part you are wearing. Check the hangtag for the certification marks before you tell a gym the helmet is UIAA or EN 12492. Sibling cards talk about those marks. Your hangtag is the one the gym can see. Do not hang a multi-tool carabiner from the helmet strap and call it a clip-in. The strap is a chin strap.

What actually fails on these two cards

The Half Dome card fails when "more than 40 grams" is converted into a finished weight. It fails when 340 g from the Tropic card is assigned to Limestone. It fails when the model cell's sentence is used as a unique part number. It fails when Medium/Large is ordered by someone who needed the centimeter range the card does not print. It fails when ventilation is read as a certification. It fails when polycarbonate and the Petzl ABS sentence are merged.

The Boreo card fails when 285 g is quoted for the M/L row. It fails when A042HA00 from the red S/M card is used to reorder white M/L. It fails when SS23 is read as a size or as a year you can shop instead of the size cell. It fails when sibling certification text is presented as a cell on this model line without the hangtag. It fails when white and Limestone are treated as the same color because both photographs are pale. They are different helmets. It fails when four headlamp clips are assumed to include the lamp.

What this comparison is not

This is not a drop-test report. Neither card prints impact joules. This is not a bike-helmet comparison. This is not a harness or a belay-device comparison. This is not a price quote. Use the buttons for the live listing. This is not a review of every Half Dome color or every Boreo color. Limestone Medium/Large, UPC 793661151357, and white Medium/Large are the two rows. This is not a video. No clip of these two color-and-size rows is embedded. A gym tour that never shows the UPC or the 295 g line would be a different subject.

So which helmet should you buy?

Buy the Black Diamond if you want Limestone, Medium/Large, the wheel and the clips, and you will carry the UPC 793661151357 because the model cell is only a sentence. Leave the gram weight blank until you weigh it. Buy the Petzl if you want white, Medium/Large, 53 to 61 cm, and the 295 g line, and you will leave 285 g and A042HA00 on the other size. Buy neither if you needed a printed certification in the Amazon cell, a bike standard, or a headlamp in the box. The size row is the decision. The sibling card is not the product.