The U.I.A.A. once set a standard defining a minimum acceptable size for an ascender’s handle. The standard included a minimum hand opening size defined by the area obtained by drawing a 20 mm. radius top circle and a 15 mm. radius bottom circle whose centers are 60 mm. apart, and then connecting the circles with the common tangents as shown in the figure. I prefer to think in terms of the overall length of the opening and the diameters of the circles, so I'll refer to this as the 95-40-30 shape.

I can't take this standard very seriously, for some of the following rather obvious reasons:

• There are a number of handleless ascenders that work perfectly well, so obviously the minimum acceptable size is 0-0-0.
• Many of the climbing systems that use handled ascenders do not use the handles directly. If one isn't going to grip the handle, then the size of the handle does not matter.
• People have different size hands, so what is so special about this size? For example, the U.I.A.A. standard size is too small an opening for my hands to completely fit inside.
• Even if a particular person with a particular size hand is going to grip the handle, the size depends on how they are going to grip it (fingertips? fingers? whole hand?)
• Given a particular hand and a particular grip, the size needed also depends on whether the hand is wearing gloves or mittens, and how large these are.

Nevertheless, I thought it might be amusing to define a few other shapes and compare the various ascenders. I made six different "handle size gages" out of wood, and used them to test the opening for each handled ascender in my collection. All of these were designed by connecting the tangents of two circles in the same manner as the U.I.A.A. defined their handle standard. In addition to the U.I.A.A. gage, I made the following gages:

Needless to say, these sizes are completely arbitrary, and I don't believe that I can justify this as being a very good set. "near misses." Second, since none of the ascenders accommodated the 120-50-40 gage, it was clearly too large to be meaningful. In 2015 I made four more gages with intermediate sizes, but one of these, the 115-40-35, was still too large for any of my ascenders to accommodate it. Some of the gages are tapered (the circle at one end is larger than the other), and these columns in the table are shaded blue.

Now for the results. A green dot indicates a fit with no problems, while half a dot indicates a fit on only one side of a dual-handled ascender. A yellow dot indicates that the gage only fit in an unusual way, such as in a particular ascender configuration not normally used for ascending (e.g., if the cam safety was not in the locked position). A green dot with an orange bar indicates that the gage barely fit, while gray dot indicates that the gage barely missed fitting. I used the symbol to emphasize a no-fit situation that some people might find surprising, just to show that I didn't omit a green dot by accident.

In the ID column for the Handled Eccentric Cam Ascenders, I used a red background for cast-frame ascenders, green for milled-frame ascenders, and blue for stamped-frame ascenders. Magenta indicates a double-rope ascender.

Handled Eccentric Cam Ascenders
Picture	ID	Device	U.I.A.A. 90-40-30	60-20-20	70-25-25	80-30-30	90-30-30	100-30-30	105-35-30	110-35-35	115-40-35	120-50-40
	211 2205	Advanced Base Camp
	2308	Alpidex Move Up
	123	Altius, Version A
	257	Altius, Version B
	2340	Al’turs (Альтурс), Version A
	2164 2905	Al’turs (Альтурс), Version B
	2165	Al’turs (Альтурс), Version C
	1942	Al’turs (Альтурс), Version D
	3639	Al'turs Aktru (Альтурс Актру)
	2187	Anthron AD-10, Version A
	155	Anthron AL-15, Version B
	2188	Anthron AD-10, Version C
	156/2189	Anthron AD-10 & AL-15, Version D
	2113/2114	Anthron AD-10 & AL-15, Version E
	194/195	Anthron AD-10 & AL-15, Version F
	2323	Asol, Version A
	2358 2370	Asol, Version B	Blocked by finger ledge.
	3478	Asol, Version C	Blocked by finger ledge.
	2052	Beal Hands Up
	2986	Венто
	1995/1996	Black Diamond Index
	2325	Blanzo
	1589	Brasovia
	2977/2978	Camnal Ascension, Version A
	3475	Camnal Ascension, Version B
	151	C.A.M.P. Pilot, Version A
	2206	C.A.M.P. Pilot, Version B
	3452	C.A.M.P. Pilot, Version C
	2386/2943	C.A.M.P. Turbohand
	2944	C.A.M.P. Turbohand Pro
	3448	Centrolit, Version A
	3448	Centrolit, Version B
	3422	Centrolit, Version C
	3642	Centrolit, Version D
	3445	Chkalov Aviation Plant, Version A
	122	Chkalov Aviation Plant, Version B
	3486	Chkalov Aviation Plant, Version C
	3486	Chkalov Aviation Plant, Version D
	3635	Chkalov Aviation Plant, Version E
	1531	Clark Single-handled Dual Ascender
	1932/1972 2197	Climb Tech
	1950/1951	Climbing Technology Amelia (Knot & Rope)
	1976 2289	Climbing Technology Quick’Arbor
	1990	Climbing Technology Quick’Arbor (separated)
	2082/2183	Climbing Technology Quick Roll							Blocked by finger ledge.
	2008 2011	Climbing Technology Quick’Up, Version A
	2012 2954	Climbing Technology Quick’Up, Version B							Blocked by finger ledge.
	1997	Climb X X Ascender
	2159	Clog Expedition, Version A
	24 1910 2158	Clog Expedition, Version B
	2156	Clog Expedition, Version C
	2157	Clog Expedition, Version D
	25	Clog Expedition, Version E
	3458 3561	Clog Expedition, Version F
	1505R 1567	Clog Expedition, Version G
	1505/3562 3568	Clog Expedition, Version H
	171 1555 2007	Clog Expedition, Version I
	218 2166	Clog Expedition, Version J
	26 172 2167	Clog Expedition, Version K
	130 2226	CMI Expedition, Version A
	3431	CMI Expedition, Version B
	3437	CMI Expedition, Version C
	239 2227	CMI Expedition Double, Version A
	3438	CMI Expedition Double, Version B
	1934 1940	CMI Expedition Twin, Version A
	2279	CMI Expedition Twin, Version B
	3439	CMI Expedition Twin, Version C
	2221	CMI 5000, Version A
	2225	CMI 5000, Version B
	2222	CMI 5000, Version C
	2299	CMI 5000, Version D
	27	CMI 5000, Version E
	2220	CMI 5000, Version F
	292 2219	CMI 5000, Version G (a.k.a. 5001)
	3654	CMI 5002, Version A
	2385	CMI 5002, Version B
	28 170 1545 2224	CMI 5002, Version C
	29	CMI 5003, Version A
	3597	CMI 5003, Version B
	30 2223 3488	CMI 5004
	3454	CMI Lanyard Ascender
	31 2229	CMI Large UltrAscender, Version A
	114	CMI Large UltrAscender, Version B
	216 2230	CMI Large UltrAscender, Version C
	246	CMI Large UltrAscender, Version D
	115/116	CMI Large UltrAscender, Version D (Modified)
	3595	CMI Large UltrAscender, Version E
	32	CMI Small UltrAscender, Version A
	33	CMI Small UltrAscender, Version B
	1518 2228	CMI Small UltrAscender, Version C
	229	CMI Small UltrAscender, Version D
	34/35	CMI Small UltrAscender, Version D (Modified)
	3596	CMI Small UltrAscender, Version E
	2954	Cypher, Version A							Blocked by finger ledge.
	2968/3409	Cypher, Version B							Blocked by finger ledge.
	3530/3531	Danger Buddies
	220	Edelrid Elevator
	3507	Edelrid Hand Cruiser
	2369	Edelweiss AS16
	3413, 3414	Epic Peak
	258	Fixe Capitan
	3591/2359	Fusion Voltron, Version A
	2910/2970	Fusion Voltron, Version B
	2322	GM Climbing, Version A
	3423	GM Climbing, Version B
	1973	Good Makings
	1998 2193	GrandWall
	1981/1982 2087/2088	Grivel A&D, Version A
	2337/2974	Grivel A&D, Version B
	2327/2980	Grivel A1
	3503/3504	heightec Pulsar X-Cam D40L/D40A	(but only upside-down!)
	256 2093	heightec-PMI Pulsar D40, Version A	(but only upside-down!)
	1500 2094 2212	heightec-PMI Pulsar D40, Version B	(but only upside-down!)						(but only upside-down!)
	1541	Hugh Banner, Version A
	199	Hugh Banner, Version B
	3640	Interalp, Version A
	2341	Interalp, Version B
	3444	Izhevsk Mechanical Plant Peak (ПИК)
	145 2211	International Safety Components, Version A
	287	International Safety Components, Version B
	2024 2209	International Safety Components RP240
	1551	Jumar, Version A
	3581	Jumar, Version B
	1576 2172	Jumar, Version C
	136	Jumar, Version D
	2351 2352	Jumar, Version E
	236 1506 1549 1550 2001	Jumar, Version F
	36 37 272	Jumar, Version G
	38 293 1547 1911 2171 2173 2174	Jumar,Version H
	1535	Jumar, Version I
	118	Jumar, Version J
	39 297 2067	Jumar 78, Version A
	40	Jumar 78, Version B
	41	Jumar 78, Version C
	265 270 285 1532 1905	Jumar 78, Version D
	42 1908	Jumar 78, Version E
	271 2175 2278	Jumar, Fritschi
	1967 2177	Jumar, Swiss Rescue
	1968 2285	Jumar Tree
	273 2176	Jumar, WAG
	1905	Jumar 79, Modified Version D
	2972	Kailas Vector
	2365	Kao (カ奥)
	3485	Kailas Vector-L
	223	Kong-Bonaiti, Version A
	139 2199 2202	Kong-Bonaiti Lift
	22 1566 1579	Kong-Bonaiti Modular With Caver Handle
	23 230 269	Kong-Bonaiti Modular With Climber Handle
	23 230 269 2381 3407	Kong-Bonaiti Modular With Dual Handle
	1516	Kong-Bonaiti double rope
	1552 2103	Kong Futura (Large Grip)
	299	Kong Futura (Small Grip)
	2200	Kong Lift, Version A
	2016/2017	Kong Lift, Version B
	249 2201	Kong Procave
	1523 2291	Kong Trender
	1529 2292	Kong Twin, Version A
	3496	Kong Twin, Version B
	210 2290	Kong Twin, Version C
	3421	Krasnoyarsk TV Factory (Красноярский Завод Телевизоров)
	2355	Kratos
	1533	Krok, Version A
	1565	Krok, Version B
	2090	Krok, Version C
	2089	Krok, Version D
	1580/1581	Krok, Version E
	2995/2996	Krok, Version F
	2997/2998	Krok, Version G
	2999	Krok, Version H							Blocked by trigger.
	3400	Krok, Version I							Blocked by trigger.
	3401	Krok, Version J /w Elevon +
	3402	Krok, Friendship-2
	3638	Likhachev Automobile Plant (Автомобильный завод имени Лихачева)
	1952 2195	LACD
	2937	Lixada, Version A
	3477	Lixada, Version B
	162/ 165	Lucky Pern AD-10 & AL-15
	2922/3410	Magideal
	3625	Metolius
	2058	Molot
	3650	MSA Safety, Version A
	3651	MSA Safety, Version B
	3652	MSA Safety, Version C
	2363	Naxen
	3490	Never Stop	Blocked by finger ledge.
	2362	Newdoar
	2014	NTR, Version A
	2324/3412	NTR, Version B
	201 2198	Omni USA
	2964	Paliston
	2105	Petzl Ascension, Version A
	2031 2183	Petzl Ascension, Version B
	43	Petzl Ascension, Version C
	296 1902 1906 2043	Petzl Ascension, Versions D1 & D2
	3469	Petzl Ascension, Version D, Vendor Modified
	1513 1554 1946	Petzl Ascension, Versions E1 & E2
	44	Petzl Ascension, Versions F2
	45 1514 1907 2353	Petzl Ascension, Versions G1 & G2
	1507L 1568 1569	Petzl Ascension, Version H
	1507R 2184	Petzl Ascension, Version I
	46 2185	Petzl Ascension, Version J
	1901	Petzl Ascension, Version K
	1571	Petzl Ascension, Version L
	169 2054	Petzl Ascension, Version M
	2924	Petzl Ascension, Version M†
	266 1900 2925	Petzl Ascension, Version N
	264	Petzl Ascension, Version N†
	127 2186	Petzl Ascension, Version O
	298 2112	Petzl Ascension, Version P (B17SLN, B17SRG)
	2010 2065	Petzl Ascension, Version Q (B17ALA, B17ARA)
	275 2278	Petzl Ascentree, Version A
	2041	Petzl Ascentree, Version B
	1536	Petzl Ascentree, Version A (half)
	3455	Petzl Ascentree, Version B (half)
	47 2110 2182	Petzl Pompe, Version A
	241 2110	Petzl Pompe, Version B
	2310	PMI Cat, Version A
	164 2163	PMI Cat, Version B
	157 2210	PMI Puma
	2021	Proverti CD 211 & CD 212
	2022	Proverti CD 211L & CD 212L
	3571	Raveltik Sherpa
	1587 2194	Rock Empire
	2305	Roloff, Version A
	3547	Roloff, Version B
	167 2342	Roloff, Version C
	2305	Roloff, Version D
	2040 2181	Roloff, Version E
	48	Roloff (Modified, Version A)
	2179	Roloff (Modified, Version B)
	2392	Roloff (Modified, Version C)
	3446	Russian, Homemade
	3586	S.E.Peak SA–203R
	3588	S.E.Peak SA–205D
	2026	Singing Rock Lift, Version A
	2919/2920	Singing Rock Lift, Version B
	51 2214	Single Rope Technique Equipment Caver, 8-11 mm
	52 53 2216	Single Rope Technique Equipment Caver, 8-15mm
	50 2215	Single Rope Technique Equipment Climber
	54	Single Rope Technique Equipment A1 Explorer, Version A
	2213	Single Rope Technique Equipment A1 Explorer, Version B
	3483	Single Rope Technique Equipment A1 Explorer, Version C
	147	Single Rope Technique Equipment A1 EXP 6 Large Explorer
	2217 2218	Single Rope Technique Equipment / Rollgliss / DBI Sala A1 EXP 6L & 6R
	3620/3621	Skylotec
	1933 2192	SOB, Version A
	2051	SOB, Versions B
	2057	SOB, Version C
	1941 1953/1954	Spelet Horní
	1956	Spent Ruční
	2961	Strmeň Žiara
	2364	SunniMix
	2326	SUT
	2000	Tokyo Top
	1991	Trango
	2025	Trango Passport
	3590	Troll
	3448	Centrolit, Version A
	2921	Tupa
	2929	Turin (Турин), Version A
	2934	Turin (Турин), Version B
	2926	Unknown Chinese
	3572	Unknown Czech
	3636	Unknown Russian
	2161	Uola, Version A
	49 2160	Uola, Version B
	2162	Uola, Version C
	178	Ural Alp 10.32, Version A
	188	Ural-Alp 10.32, Version B
	2367	Ural Alp 10.32, Version C
	1992	VauDe, Version A
	1993	VauDe, Version B
	133/134 2190/2191	VauDe, Version C
	1559/1560	Vento (Венто) Ascension
	187	Vertical (Вертикаль), Version A  (a.k.a. Kirov)
	2932	Vertical (Вертикаль), Version B
	2931	Vertical (Вертикаль), Version C
	3577	Vertical (Вертикаль), Version D
	2311	Vertical (Вертикаль), Version E
	3484	Vertical (Вертикаль) Butterfly (Бабочка)
	3619	Vertical Big Wall
	2104	Walkosz i Spółka
	2938 2939	Xinda, Version A
	2965	Xinda, Version B
	3441	Xinda, Version C
	291 2208	Yates Big Wall
	1939 2196	Yoke
	3519	Yurginsky Machine-Building Plant
	3657	Zaporizhzhian
	3481	Zeluga
	2366	Z&W, Version A
	2366	Z&W, Version B
Handled Type 1 Lever Cam Ascenders
Picture	ID	Device	U.I.A.A. 90-40-30	60-20-20	70-25-25	80-30-30	90-30-30	100-30-30	105-35-30	110-35-35	115-40-35	120-50-40
	219 2106	Black Diamond nForce
	3564/2959	C.A.M.P.
	55	Kong-Bonaiti, Version A
	3633	Kong-Bonaiti, Version B
	56 1556 2107	Kong-Bonaiti, Version C
	58	Leningrad Experimental Shipyard, Version A
	3529	Leningrad Experimental Shipyard, Version B
	3644	Leningrad Experimental Shipyard, Version C
	3637	Leningrad Experimental Shipyard, Version D
	3539	Tashkent Aviation Plant
Handled Rocker-Arm Ascenders
Picture	ID	Device	U.I.A.A. 90-40-30	60-20-20	70-25-25	80-30-30	90-30-30	100-30-30	105-35-30	110-35-35	115-40-35	120-50-40
	120	Ural Alp Handled
	144 2273	USHBA Mountain Works Handled