BTinNYC 

I like look of these, with the big central bump (aero!) and eyeballs for eyelets, are they a touring rim? 36 hole.

JohnDThompson 

The rim is patterned after the Weinmann Alesa rim. The raised center section is cosmetic, the domed eyelets allow the nipple to seat in-axis with the spoke.

scarlson 

Geez, it almost looks like you could retrofit a rod-brake bike with these. I bet it would work and braking performance would be improved.

BTinNYC 

Thanks gents.
scarlson , your vintage is really old! Shiny stuff to go with those rims on a 70's era boulevardier.

T-Mar

The raised centre section is more than just cosmetic. It adds some rididity and makes mounting tyres easier.

w/o stands for "wired-on", the correct terminology for what are erroneously called "clinchers". Wired-on tyres have rigid wire or flexible cord hoops encased in the bead. True clinchers have enlarged rubber beads without the wire or cord hoop. In some markets true cllnchers are called beaded edge tyres, which is abbreviated b/e.

HP stands for "high pressure". The rims should have a bead or hook on the inside of the outer edge of the the sidewall. This facilitates retention of high pressure tyres, particularly those with flexible beads.

dddd

I remember during the late 1970's into the eighties when 90 or even 100psi 27" and 700c wired-on tires were OEM-fitted to hookless, box-style, single-walled Japanese rims, and I am fairly sure that many of these rims had an HP identifier stamp.
The tires were often labeled as 1-1/8" wide or an equivalent 28mm, but only measured 24-25mm inflated on those ~15-16mm internal width rims.
The rims were dimensioned such that tire blow-offs simply didn't happen.

T-Mar

You're correct. My mistake. Now that I think of it, HP was only for high pressure, wire bead tyres. Not folding tyres with flexible beads.

BTinNYC 

Aha. Straight walls with internal width at 20mm.

repechage

these predated folding tires.
these Araya rims built up easier than the Weinmann originals I thought.

the rim shape did add a bit of cross sectional area.

when they were available, they were a 27" rim.
maybe 700c for other markets?

dddd

Weinmann touring rims from the early 1970's could be prone to loose diameter tolerances such that the built wheel might not contain even a brand-new wire-bead tire at pressures above 70psi.
The Japanese versions didn't seem to have any such problem.
However, later, narrower, double-walled, semi-hooked Araya rims did not always retain wire or folding tire beads at the 90-100psi that I tried running on them. Seems that aged tire's bead rubber didn't sufficiently engage/grip the semi-circular nubs that passed for bead hooks and I suffered blow-offs at the bottom of steep descents using both wired and folding tires. Luckily those front tires both thumped on the fork leg several times before blowing off, so both times I stayed upright. Btw, those were two different tires on two different front, narrow, Araya rims. Tires were Matrix wired and Specialized or Avocet folding, 700x25 (actually about 21mm) and 23mm, respectively.

Folding tires first appeared around the mid-70's, The Michelin Elan tire and Mavic Module-E rim were apparently made for each other, though only the Mavic rim could be considered a complete success and worthy product.
Rigida followed up with their narrow, bendage-prone 13-19 rim and Super-Champion soon came out with their wider/tougher Gentleman rim. Japanese versions from Araya and Ukai also soon arrived.
All of these narrow rims were double-walled and eyeletted.

RCMoeur 

That looks to be an Araya 7B rim.

Graphic stolen appropriated from another site and annotated: