Mail Stop 3030
                                                                   June 19,
2018


     Via E-mail
     Dean Irwin
     Chief Executive Officer
     Ra Medical Systems, Inc.
     2070 Las Palmas Drive
     Carlsbad, CA 92011

            Re:     Ra Medical Systems, Inc.
                    Draft Registration Statement on Form S-1
                    Submitted May 21, 2018
                    CIK No. 0001716621

     Dear Mr. Irwin:

            We have reviewed your draft registration statement and have the
following comments. In
     some of our comments, we may ask you to provide us with information so we
may better
     understand your disclosure.

            Please respond to this letter by providing the requested
information and either submitting
     an amended draft registration statement or publicly filing your
registration statement on
     EDGAR. If you do not believe our comments apply to your facts and
circumstances or do not
     believe an amendment is appropriate, please tell us why in your response.

           After reviewing the information you provide in response to these
comments and your
     amended draft registration statement or filed registration statement, we
may have additional
     comments.

     Prospectus Summary, page 1

     1.     The basis for your statement that DABRA is "cost-effective for
healthcare payors and
            providers" is unclear. Please revise to provide support for this
claim, and specifically
            address the lack of reimbursement codes.

     2.     Where you elect to highlight the lack of serious adverse events
associated with your
            products, also disclose, if true, that your basis for this
assertion is data from your pivotal
            study in 2017 on 64 patients, in which you measured adverse events
at the time of the
            procedure. Disclose that you only followed 38 patients to 180 days
after the study and
            discuss whether you assessed them for adverse events at that time.
Also, if you choose to
 Dean Irwin
Ra Medical Systems, Inc.
June 19, 2018
Page 2

       highlight the lack of serious adverse events, balance your disclosure
with the disclosure
       on page 32 suggesting that other types of adverse events have occurred,
or advise.

3.     You claim that your laser products enhance patients' quality of life and
save limbs from
       amputation, among other benefits. The bases for these claims appear
subjective and/or
       speculative. Please revise to present these claims as your belief or
advise if you have
       objective supporting evidence.

4.     Make sure that you explain terminology to the degree necessary for an
average reader to
       understand your products and business. While your disclosure eventually
describes most
       terms specifically, your summary may benefit from elaboration of certain
terms which
       may not be clear from the context, like fluoroscopy, revascularization
and collimation.

Our Strategy, page 2

5.     If you elect to highlight your "proprietary product technology," revise
to disclose that the
       lasers upon which your products are based are not covered by patents you
own.

Implications of Being an Emerging Growth Company, page 5

6.     Please supplementally provide us with copies of all written
communications, as defined
       in Rule 405 under the Securities Act, that you, or anyone authorized to
do so on your
       behalf, present to potential investors in reliance on Section 5(d) of
the Securities Act,
       whether or not they retain copies of the communications.

Risk Factors, page 12

7.     Refer to the risk factor on page 13. Clarify whether you have any
reimbursement from
       third-party payors and how a lack thereof will impact DABRA's
marketability. Also,
       discuss in your business section whether you have any ongoing efforts to
establish
       specific reimbursement codes related to DABRA treatments.

We face credit and compliance risk . . ., page 22

8.     It is difficult to assess the risk presented because there does not
appear to be any
       additional disclosure about your distribution network. Please clarify
the scope of the risk
       by discussing relevant details about your distributors' locations or the
volume of your
       business represented by distribution channels or other relevant
information.
 Dean Irwin
Ra Medical Systems, Inc.
June 19, 2018
Page 3

We could be subject to claims based on defects . . ., page 24

9.     We note your disclosure on page 25 that you face potential liability to
existing
       shareholders relating to past corporate transactions. Please clarify the
scope of any
       material potential liability and discuss which "requirements of
applicable law" are at
       issue. Also, provide us your analysis of whether the disclosed past
transactions could
       materially impact your intended reincorporation in connection with this
offering.

EBITDA and Adjusted EBITDA, page 75

10.    Please revise the discussion of Adjusted EBITDA limitations to describe
why the loss on
       abandonment of facilities is included as an adjustment in the non-GAAP
measure.

Critical Accounting Policies and Estimates, page 79

Stock-Based Compensation expense, page 80

11.    When pricing information for this offering is available, please tell us
the significant
       reasons for any material differences between your last common stock fair
value
       determination and the mid-point of the estimated IPO price range
including all material
       positive and negative events occurring during the period which could
reasonably
       contribute to variances in fair value.

Business, page 84

12.    Please revise to clarify whether the various treatments address the
vascular disease itself
       or side effects thereof. Specifically, it is not clear whether the
plaque blockages are the
       disease or just result from the disease. In this respect, it appears
that some treatments
       attempt to support the vein while others clear the blockage. Please
revise if these
       differences would affect your discussion of your business and the
competitive landscape.

DABRA, page 84

13.    We note your disclosure in the third full sentence on page 85 that your
DABRA product
       can be used in conjunction with other treatments. Revise to disclose how
often your
       products are used in conjunction with other treatments and balance your
disclosure
       concerning the competitive advantages your product offers over these
competing
       technologies.
 Dean Irwin
Ra Medical Systems, Inc.
June 19, 2018
Page 4

14.    Balance your disclosure concerning the possible immunosuppressive
effects of your
       DABRA product with your disclosure under the heading Immunotherapeutic
Benefits on
       page 87.

Pre-Marketing Studies, page 91

15.    Revise to clarify whether the data cited in the second paragraph
regarding your DABRA
       study results was measured over the same timeframe as that used in the
predicate device's
       study, which results you also cite.

16.    Disclose whether the lesion size and method of angiograph analysis
differ meaningfully
       from standard practice in commercial application.

Patents, page 96

17.    File your material confidentiality and assignment agreements, given your
disclosure here
       and on page 43.

Management, page 106

18.    Clarify whether you had a person acting as your principal financial
officer prior to April
       2018.

Employment Arrangements with Our Named Executive Officers, page 114

19.    We note you intend to enter into new offer letters or employment
agreements with your
       named executive officers. File the existing agreements, and, if
applicable, the new
       agreements, as exhibits.

Security ownership of certain beneficial owners and management, page 125

20.    It does not appear that selling shareholders will participate in this
offering. As such,
       please clarify the purpose of including two columns disclosing the
number of shares each
       beneficial owner owns. It is unclear why that number would differ before
and after the
       offering. Also, provide the footnote disclosure suggested by the numbers
following each
       owner's name or advise.
 Dean Irwin
Ra Medical Systems, Inc.
June 19, 2018
Page 5

Shares eligible for future sale, page 131

21.    Revise to clarify what "securities convertible into or exchangeable for
[y]our common
       stock" you currently have outstanding and where disclosure concerning
these securities is
       located in your prospectus.

Note 2   Significant Accounting Policies

Fair value measurements, page F-9

22.    With respect to the stock-based compensation liability, please revise
the filing to disclose
       quantitative information about the significant unobservable inputs
underlying the Level 3
       fair value measurement, including the estimated fair value of your
common stock, as of
       each balance sheet date. Refer to ASC 820-10-50-2(bbb).

23.    You indicate on page F-21 that the estimated fair value of your common
stock as of the
       date of grant is determined using recent equity issuances, if available,
or if there are no
       recent issuances available, the valuation is estimated using both the
income and market
       approaches. Please revise the filing to clarify if your stock-based
compensation liability
       as of each period end was estimated based on a recent common stock
valuation or a
       combination of the income and market approaches.

24.    Please revise this note to provide a reconciliation of the opening and
closing balances of
       your Level 3 fair value measurements for each balance sheet date
provided. Refer to ASC
       820-10-50-2(c).

Revenue Recognition

Product Sales, page F-9

25.    You discuss on page 79 that revenue from product sales is presented net
of provisions for
       estimated charge backs, rebates, expected returns and cash discounts.
Please revise this
       note to describe the nature and significant terms of all discounts,
incentives, returns and
       other concessions offered to your customers. If these programs are
significant, expand
       your critical accounting policy discussion to address the uncertainties
associated with the
       methods, assumptions, and estimates underlying your accounting for these
programs.

Multiple Element Arrangements, page F-10

26.    You indicate that in cases where VSOE cannot be determined you use
third-party
       evidence of selling price, if available, or best estimated selling
price. Please revise your
 Dean Irwin
Ra Medical Systems, Inc.
June 19, 2018
Page 6

       disclosure to provide a discussion of the significant factors, inputs,
assumptions, and
       methods used to determine selling price. Refer to ASC 605-25-50-2(e).

Lease Arrangements, page F-10

27.    Please revise to provide the disclosures required by ASC 840-10-50-4 and
840-20-50-4
       for your operating leases.

Note 3   Restatement and Reclassifications, page F-15

28.    We note your disclosures relating to the accounting error surrounding
the awards to
       Optionees. To help us better understand your revised accounting, please
address the
       following:

              Describe to us in detail the circumstances surrounding your
issuance of awards to
              Optionees that were not validly authorized, including how you
determined the
              awards were not authorized and your conclusion that the
communicated awards
              were not outstanding options that should be accounted for
pursuant to ASC 718-
              10.
              Discuss for us your conclusion that your contractual obligation
to the Optionees
              should be accounted for as a liability remeasured at each
reporting date and tell us
              the authoritative guidance on which you based that conclusion.
              Clarify for us whether you have now obtained valid authorization
or tell us the
              steps you are taking to obtain valid authorization and explain
how valid
              authorization would change your accounting.

Item 15. Recent Sales of Unregistered Securities, page II-2

29.    Revise to name the persons or identify the classes of persons to whom
the securities were
       sold.
 Dean Irwin
Ra Medical Systems, Inc.
June 19, 2018
Page 7

        You may contact Eric Atallah at (202) 551-3663 or Kevin Kuhar,
Accounting Branch
Chief, at (202) 551-3662 if you have questions regarding comments on the
financial statements
and related matters. Please contact Caleb French at (202) 551-6947 or me at
(202) 551-3528
with any other questions.


                                                          Sincerely,

                                                          /s/ Amanda Ravitz

                                                          Amanda Ravitz
                                                          Assistant Director
                                                          Office of Electronics
and Machinery

cc:    Martin J. Waters, Esq.
       Wilson Sonsini Goodrich & Rosati, P.C.